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The article presents an overview of the National Strength and Conditioning Association's Gary A. Dudley Memorial Paper: Scientific Manuscript Excellence Honor award. A profile of Gary A. Dudley, who championed the concept of integrated biology and had a celebrated career in the field of strength and conditioning, is presented.

Ratanapinunchai, J and Madeeyoh, I. Differences in electromygraphic activity of the middle and the lower serratus anterior fibers during open and closed kinematics exercises. J Strength Cond Res 36(7): 1788–1792, 2022—This paper seeks to determine differences in muscle activation between the middle (MSA) and the lower serratus anterior (LSA) fibers during 3 exercises. Fifteen healthy men were recruited for the study. Bench push-up plus (BPUP), unstable BPUP (UPUP), and resisted shoulder flexion (RSF) with 10 repetitions at maximum weight were tested. The normalized electromyographic (EMG) activity of the MSA and the LSA was recorded during isometric scapular protraction for BPUP and UPUP or at 150° shoulder flexion for RSF. Normalization was calculated using maximum voluntary isometric scapular protraction activity (%EMG). The results showed that the ratio of %EMG of MSA:LSA was higher than one in BPUP (1.41 ± 0.36) and UPUP (1.81 ± 0.47), but less than one (0.86 ± 0.27) in RSF. These ratios were statistically significantly different (p < 0.05). The activity of MSA and LSA in RSF was significantly (p < 0.002) higher than that of BPUP and UPUP (%EMG of the MSA = 80.53 ± 26.07, 64.75 ± 23.19 and 55.62 ± 25.56 for the RSF, BPUP, and UPUP, respectively; %EMG of LSA = 95.54 ± 24.15, 50.71 ± 26.32, and 32.26 ± 16.14 for the RSF, BPUP, and UPUP, respectively). There was no difference in the %EMG of MSA and LSA between BPUP and UPUP. The MSA worked more than the LSA in the push-up plus (PUP), but the opposite was found in the RSF exercise. The study suggests different functions of the MSA and the LSA. Different exercises should be used, including a PUP for the MSA and RSF for the LSA, or a combination to emphasize both parts of the SA. [ABSTRACT FROM AUTHOR]

The article reports on research which was conducted to examine the validity of estimating anaerobic power in college-aged students using anthropometric data and a paper and pencil test. Researchers determined peak power (PP) and mean power (MP) in 157 subjects using a standard Wingate anaerobic test. They found that valid estimates for PP and MP could be obtained from anthropometric data and a single question paper and pencil test.

In a 1989 position paper, the National Strength and Conditioning Association (NSCA) recommended that male and female athletes be trained in a similar manner with regard to modalities and program design. To determine whether that recommendation is being followed, this study examined training practices of coaches of male and female athletes at the interscholastic level. Electronic surveys regarding strength training practices were distributed to head coaches of boys' football, basketball, soccer, and baseball and girls' volleyball, basketball, soccer, and softball in the states of Texas and Wisconsin. Overall, 85% of coaches (n = 85) reported that they require their athletes to strength train. There was no difference in whether strength training was required based on athlete sex (X²=0.16, df51, p50.69) or the sex of the coach (X²= 0.63, df=1, p=0.43). The majority (67%) of teams strength trained once weekly during the season and 21% trained twice weekly. In the off-season, only 12% of teams trained once weekly, whereas 44% of teams strength trained 2 times per week and 29% 3 times weekly. The most common types of lift performed for both sexes were "bodyweight exercises," followed by "dumbbell presses," bench press, back squats, and front squats. Both female and male athletes trained most commonly at 4-8 repetition and 9-12 repetition ranges. In contrast to previous studies and in accordance with the NSCA recommendation, it seems that the high school coaches surveyed in this work largely train male and female athletes in a similar fashion with regard to training frequency, intensity, and modalities. [ABSTRACT FROM AUTHOR]

This systematic review and meta-analysis examined the impact of exercise-induced muscle damage (EIMD) on cycling performance. The primary outcome measure was cycling performance, whereas secondary outcome measures included creatine kinase (CK), delayed-onset muscle soreness (DOMS), and muscular contractions. Data were extracted and quantified through forest plots to report on the standardized mean difference and p values. The meta-analysis showed no significant change in oxygen consumption at 24-48 hours (p > 0.05) after the muscle damage protocol, although ventilation and rating of perceived exertion significantly increased (p < 0.05) during submaximal cycling protocols. Peak power output during both sprint and incremental cycling performance was significantly reduced (p < 0.05), but time-trial and distance-trial performance showed no change (p > 0.05). Measures of CK and DOMS were significantly increased (p < 0.05), whereas muscular force was significantly reduced following the muscle-damaging protocols (p < 0.05), confirming that cycling performance was assessed during periods of EIMD. This systematic review showed that EIMD affected both maximal and submaximal cycling performance. Therefore, coaches should consider the effect of EIMD on cycling performance when implementing unaccustomed exercise into a cycling program. Careful consideration should be taken to ensure that additional training does not impair performance and endurance adaptation. [ABSTRACT FROM AUTHOR]

Insulin-like growth factor 1 (IGF-I) has been implicated as a biomarker of health and body composition. However, whether changes in body composition are associated with changes in IGF-I is unclear. Therefore, we examined the relationship between body composition changes (i.e., fat mass and lean mass) and total serum IGF-I levels in a large cohort of young men (n = 809) and women (n = 397) attending US Army basic combat training (BCT). We measured body composition using dual energy x-ray absorptiometry and total serum IGF-I levels during week 1 and week 9 of BCT. We found that pre-BCT lean mass (r = 0.0504, p = 0.082) and fat mass (r = 0.0458, p = 0.082) were not associated with pre-BCT IGF-I. Body mass, body mass index, body fat percentage, and fat mass decreased, and lean mass increased during BCT (all p < 0.001). Mean (±SD) IGF-I increased from pre-BCT (176 ± 50 ng⋅ml-1) to post-BCT(200 ± 50 ng⋅ml-1, p < 0.001). Inspection of the partial correlations indicated that even when considering the unique contributions of other variables, increases in IGF-I during BCT were associated with both increased lean mass (r = 0.0769, p = 0.023) and increased fat mass (r = 0.1055, p < 0.001) with no sex differences. Taken together, our data suggest that although changes in IGF-I weakly correlated with changes in body composition, IGF-I, in isolation, is not an adequate biomarker for predicting changes in body composition during BCT in US Army trainees. [ABSTRACT FROM AUTHOR]

(a) Ascertain whether lower muscle mass, strength (1 repetition maximum [1RM]), and power (Pmax) in middle-aged women who are breast cancer survivors (BCS), when compared with women of a similar age never diagnosed with cancer (WNC), are related with lower walking speed (WS). (b) Ascertain whether changes in WS are associated with changes in muscle mass, 1RM, and (or) Pmax after resistance training (RT) in middle-aged BCS. A cross-section study was performed. Twenty WNC and 21 BCS were evaluated for lean mass of legs (LLM), 1RM (knee extension), muscle quality index (MQI = 1RM/LLM), Pmax (maximum muscle power-knee extension), and fast WS (10 and 400-meters). Randomized clinical trial was performed. The BCS were randomly divided into the control group (n = 9) and the RT group (n = 11). Breast cancer survivors exhibited lower 1RM (24.2%, p < 0.001), Pmax (30.6%, p < 0.001), MQI (22.2%, p = 0.001), and WS (10-m = 17.0%, p < 0.001 and 400-m = 10.5%, p = 0.002) than WNC. Resistance training increased 1RM (31.6%, p = 0.001), MP (29.0%, p = 0.012), MQI (28.5%, p = 0.008), and WS (10-m = 9.4%, p = 0.009 and 400-m = 6.2%, p = 0.006) in BCS. The changes in WS were positively associated with 1RM (10-m = 68%, p = 0.001 and 400-m = 37%, p = 0.036) and Pmax (10-m = 56%, p = 0.005 and 400-m = 40%, p = 0.027) and MQI (10-m = 63%, p = 0.043 and 400-m = 37%, p = 0.035). Resistance training-induced gains in muscle strength and power mediate the improvement in WS in middle-aged BCS. Resistance training is an effective strategy to improve WS in middle-aged BCS. [ABSTRACT FROM AUTHOR]

This systematic review and meta-analysis compared muscle damage markers and physical performance measures between 2 bouts of multiarticular exercises and determined whether intensity and volume of muscle-damaging exercises affected the outcomes. The eligibility criteria consisted of (a) healthy male and female adults; (b) multiarticular exercises to cause muscle damage across 2 bouts; (c) outcome measures were compared at 24-48 hours after the first and second bouts of muscle-damaging exercise; (d) at least one of the following outcome measures: creatine kinase (CK), delayed onset of muscle soreness (DOMS), muscle strength, and running economy. Study appraisal was conducted using the Kmet tool, whereas forest plots were derived to calculate standardized mean differences (SMDs) and statistical significance and alpha set a 0.05. After screening, 20 studies were included. The levels of DOMSand CK were significantly greater during the first bout when compared with the second bout at T24 and T48 (p<0.001;SMD = 0.51-1.23). Muscular strength and vertical jump performance were significantly lower during the first bout compared with the second bout at T24 and T48 (p ≤ 0.05; SMD = -0.27 to -0.40), whereas oxygen consumption and rating of perceived exertion were significantly greater during the first bout at T24 and T48 (p<0.05; SMD=0.28-0.65) during running economy protocols. The meta-analyses were unaffected by changes in intensity and volume of muscle-damaging exercises between bouts. Multiarticular exercises exhibited a repeated bout effect, suggesting that a single bout of commonly performed exercises involving eccentric contractions may provide protection against exercise-induced muscle damage for subsequent bouts. [ABSTRACT FROM AUTHOR]

The origins of weightlifting and feats of strength span back to ancient Egypt, China, and Greece, with the introduction of weightlifting into the Olympic Games in 1896. However, it was not until the 1950s that training based on weightlifting was adopted by strength coaches working with team sports and athletics, with weightlifting research in peerreviewed journals becoming prominent since the 1970s. Over the past few decades, researchers have focused on the use of weightlifting-based training to enhance performance in nonweightlifters because of the biomechanical similarities (e.g., rapid forceful extension of the hips, knees, and ankles) associated with the second pull phase of the clean and snatch, the drive/thrust phase of the jerk and athletic tasks such as jumping and sprinting. The highest force, rate of force development, and power outputs have been reported during such movements, highlighting the potential for such tasks to enhance these key physical qualities in athletes. In addition, the ability to manipulate barbell load across the extensive range of weightlifting exercises and their derivatives permits the strength and conditioning coach the opportunity to emphasize the development of strength-speed and speed-strength, as required for the individual athlete. As such, the results of numerous longitudinal studies and subsequent meta-analyses demonstrate the inclusion of weightlifting exercises into strength and conditioning programs results in greater improvements in force-production characteristics and performance in athletic tasks than general resistance training or plyometric training alone. However, it is essential that such exercises are appropriately programmed adopting a sequential approach across training blocks (including exercise variation, loads, and volumes) to ensure the desired adaptations, whereas strength and conditioning coaches emphasize appropriate technique and skill development of athletes performing such exercises. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is Available in the Text. Chang, C-C, Chang, C-M, and Shih, Y-F. Kinetic chain exercise intervention improved spiking consistency and kinematics in volleyball players with Scapular Dyskinesis. J Strength Cond Res 36(10): 2844–2852, 2022—Scapular dyskinesis (SD) is a common problem among volleyball players with chronic shoulder pain. This randomized controlled study examined the effectiveness of kinetic chain (KC) training on neuromuscular performance of the scapula and trunk during volleyball spikes. Forty volleyball players with SD and chronic shoulder pain received 4 weeks of KC training or the conventional shoulder exercise training (CT). Shoulder pain was assessed using the visual analogue scale (VAS) every week. The kinematics and muscle activation of the shoulder and upper trunk, and proprioceptive feedback magnitude (PFM) for scapular movement consistency, were recorded at the maximum shoulder flexion (T1) and ball contact (T2) during spiking tasks. The two-way repeated measures analysis of variances was used to assess the between-group differences before and after the intervention. The results showed a significant time by group interaction for the upper trunk rotation (p < 0.001) and PFM (p = 0.03) at T2. The post-hoc test indicated that the KC group significantly increased contralateral rotation of the upper trunk (9.63 ± 4.19° vs. −4.25 ± 10.05°), and improved movement consistency (error: 8.88 ± 11.52° vs. 19.73 ± 12.79°) at T2 compared with the CT group. Significant time effects were also identified for VAS, scapular upward rotation (T1 and T2), upper trunk contralateral side-bending and PFM at T1, and upper trunk contralateral rotation at T2. In conclusion, both KC and CT training would relieve shoulder pain and improve scapular and trunk movement, whereas the KC program was more effective for increasing scapular movement consistency and upper trunk rotation during volleyball spikes. [ABSTRACT FROM AUTHOR]

Hackett, DA. Influence of movement velocity on accuracy of estimated repetitions to failure in resistance-trained men. J Strength Cond Res 36(10): 2701–2708, 2022—This study explored the accuracy in estimated repetitions to failure (ERF) and changes in mean concentric velocity (MCV) during resistance exercise. Twenty male resistance trainers (age, 26.3 ± 6.9 years; body mass, 82.0 ± 6.0 kg; stature, 178.0 ± 5.5 cm) completed 5 sets of 10 repetitions for the bench press and squat at 70% one-repetition maximum. Subjects' reported their rating of perceived exertion (RPE) and ERF after the 10th repetition of each set and then continued repetitions to momentary muscle failure (5-minute recovery between sets). Barbell velocity was assessed using a linear position transducer. For the bench press, MCV at repetitions 9–10 decreased as sets progressed (p ≤ 0.005) with a greater loss of MCV for sets 3–5 vs. set 1 (p ≤ 0.005). No significant changes in MCV variables were found across sets for the squat. Error in ERF was greater in set 1 for the bench press (p ≤ 0.005) with no differences for the remaining sets. There were no differences between sets for error in ERF for the squat. Moderate to strong relationships were found between most MCV variables and RPE and ERF, for the bench press (r s = −049 to 0.73; p ≤ 0.005). For the squat only, MCV at repetitions 9–10 was moderately related with RPE (r s = −0.33; p ≤ 0.003) and actual repetitions to failure (r s = 0.31; p ≤ 0.003). No significant relationships were found for error in ERF for either the bench press or squat. Changes in MCV across sets may influence perception of effort and performance for the bench press; however, it does not influence the accuracy in ERF for either exercise. [ABSTRACT FROM AUTHOR]

Fazio, C, Elder, CL, and Harris, MM. Efficacy of alternative forms of creatine supplementation on improving performance and body composition in healthy subjects: a systematic review. J Strength Cond Res 36(9): 2663–2670, 2022—Novel forms of creatine have appeared in the marketplace with substantial claims of improved efficacy compared to creatine monohydrate (CrM). The purpose of this study was to conduct a systematic review on alternative forms of creatine to determine (a) whether they are effective ergogenic aids and (b) whether they outperform CrM. A separate comparison was conducted to determine average cost of various forms of creatine. Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Medline, and Google Scholar were systematically reviewed according to PRISMA guidelines. The design of the review was set to answer the PICOS model (subjects, interventions, comparators, outcomes, and study design). Seventeen randomized placebo controlled clinical trials examining exercise performance outcomes and body composition were included in the analysis. Magnesium-creatine chelate and creatine citrate, malate, ethyl ester, nitrate, and pyruvate were the only forms researched in the literature. Of these studies, only 3 studies compared the alternative creatine form to CrM, making it difficult to compare efficacy to CrM. There were no consistent findings of performance enhancement among alternative forms of creatine when compared to placebo. A review of the marketplace shows that CrM is the lowest cost form of creatine. Due to the paucity of studies on alternative forms of creatine as well as high prices on the market of these alternative forms, CrM remains as the most extensively studied form of creatine that shows efficacy, safety, and lowest cost to consumer. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is Available in the Text. Leech RD, Grunseit A, and Edwards KL. Self-report and contemporaneously recorded running agreement in recreational athletes. J Strength Cond Res 36(7): 1922–1929, 2022—Accurate assessment of running exposure in research or clinical practice relies on the ability to measure the behavior validly and reliably. Self-reported physical activity (PA) (including running), although commonly used, is subject to bias. User-owned wearable technological devices provide a potential contemporaneously collected data source for validating retrospective running-specific questionnaires. This study assesses agreement between self-reported running and contemporaneously collected running data. Self-reported running and corresponding contemporaneously recorded for current (at the time of questionnaire completion) and historical (6 months prior) was collected. Concordance Correlations and Bland-Altman Limits of Agreement measured extent of agreement. Categories for Metabolic Equivalent Task (MET) hours per week were calculated from total running distance. Unweighted and weighted Kappas were used to compare classification of levels of running by the 2 data sources. Running data were collected from 139 subjects (mean age 51.1 years). Self-report data were higher than contemporaneous data. Average estimated pace from both sources were similar, with high variance in some individuals. Differences of 43.5–57.1% were reported for current mean weekly running distances for 7-day, 4-week, and 12-week running periods. The level of agreement in classification between self-report and contemporaneous running data MET/HR categories was fair (unweighted K = 0.24–0.33) to moderate (weighted K = 0.46–0.63). Compared with contemporaneous running data, runners over-estimate the frequency, distance, and duration of running in self-report. Runners tend to discount nonrunning periods and unusual runs when estimating current and historical "average" running. The opportunities and limitations of different contemporaneous running data collection methods as a PA comparator must be acknowledged. [ABSTRACT FROM AUTHOR]

Helme, M, Emmonds, S, and Low, C. Is the rear foot elevated split squat unilateral? An investigation into the kinetic and kinematic demands. J Strength Cond Res 36(7): 1781–1787, 2022—The purpose of the study was to determine the unilateral nature of the rear foot elevated split squat (RFESS). Specifically, the production of force by the rear leg was examined to better understand its role, if any, toward successful completion of the exercise. Male volunteers were recruited (n = 26, age = 23.8 ± 4.6 years, body mass = 88.1 ± 10.7 kg, and height = 1.79 ± 0.1 m), who were recreationally trained and engaged in a structured strength and conditioning program, including both bilateral and unilateral exercises, and had at least 2 years supervised training experience. Subjects participated in an incremental 5 repetition maximum protocol after familiarization. Kinetic data were recorded through 2 independent force plates, 1 integral to the floor and the second mounted on top of solid weightlifting blocks. Kinematic data were captured through 3-dimensional motion analysis. A total of 715 repetitions were analyzed, and the mean contribution of the lead foot to total vertical force production was 84.36 ± 3.6%. An almost certainly small positive correlation (rho = 0.25, confidence interval [CI] 0.18–0.33) was found between the percentage of force produced by the lead foot, with increasing exercise intensity. A most likely trivial, nonsignificant correlation (rho = −0.01, CI −0.09 to 0.06) with rear foot force production, representing the mass of the rear leg. Data from this study do not indicate that the rear foot contributes to the kinetic demands of the exercise and therefore suggests that the RFESS is a valid unilateral exercise. [ABSTRACT FROM AUTHOR]

O'Connor, FK, Doering, TM, Minett, GM, Reaburn, PR, Bartlett, JD and Coffey, VG. Effect of divergent solar radiation exposure with outdoor versus indoor training in the heat: implications for performance. J Strength Cond Res 36(6): 1622–1628, 2022—The aim of this study was to determine physiological and perceptual responses and performance outcomes when completing high-intensity exercise in outdoor and indoor hot environments with contrasting solar radiation exposure. Seven cyclists and 9 Australian Football League (AFL) players undertook cycling trials in hot conditions (≥30 °C) outdoors and indoors. Cyclists completed 5 × 4 minutes intervals (∼80% peak power output [PPO]) with 2 minutes recovery (∼40% PPO) before a 20-km self-paced ride. Australian Football League players completed a standardized 20 minutes warm-up (∼65% mean 4-minute power output) then 5 × 2 minutes maximal effort intervals. Heart rate (HR), PO, ratings of perceived exertion (RPE), thermal comfort (TC), and thermal sensation (TS) were recorded. Core (Tc) and skin temperature (Tsk) were monitored in cyclists alone. In both studies, ambient temperature, relative humidity, and solar radiation were monitored outdoors and matched for ambient temperature and relative humidity indoors, generating different wet bulb globe temperature (WBGT) for cyclists, but the similar WBGT for AFL players through higher relative humidity indoors. The statistical significance was set at p ≤ 0.05. Cyclists' HR (p = 0.05), Tc (p = 0.03), and Tsk (p = 0.03) were higher outdoors with variable effects for increased RPE, TS, and TC (d = 0.2–1.3). Power output during intervals was not different between trials, but there were small-moderate improvements in cyclists' PO and 20-km time indoors (d = 0.3–0.6). There was a small effect (d = 0.2) for AFL players' mean PO to increase outdoors for interval 4 alone (p = 0.04); however, overall there were small-moderate effects for lower RPE and TS indoors (d = 0.2–0.5). Indoor training in hot conditions without solar radiation may promote modest reductions in physiological strain and improve performance capacity in well-trained athletes. [ABSTRACT FROM AUTHOR]

Marta, C, Alves, AR, Casanova, N, Neiva, HP, Marinho, D, Izquierdo, M, Nunes, C, and Marques, MC. Suspension vs. plyometric training in children's explosive strength. J Strength Cond Res 36(2): 433–440, 2022—The aim of this study was to compare the effects of different training programs, that is, 8 weeks of suspension training (ST) or plyometric training (PT), on measures of strength and power in untrained healthy children. One hundred eighteen children (57 boys and 61 girls) aged 10–11 years (mean ± SD : 10.84 ± 0.46 years) were randomly assigned into PT (19 boys and 22 girls), ST (20 boys and 18 girls), and control (CT) (18 boys and 21 girls; no training program) group. Experimental groups were trained twice a week for 8 weeks. Countermovement jump, standing long jump, medicine ball throw, and 20-m sprint were measured at baseline and after intervention. The results showed a significant group effect on training-induced responses (F = 10.26; p < 0.01; η p 2 = 0.33), with clear improvements from pre- to posttraining in PT and ST. Regardless of training group, no differences were found in boys and girls (F = 0.70; p = 0.62; η p 2 = 0.03). After 8 weeks of training, PT and ST showed increased performances in 1-kg (mean ± CI 95%; 0.18 ± 0.05 and 0.19 ± 0.05 m) and 3-kg (0.12 ± 0.08 and 0.12 ± 0.09 m) medicine ball throws and 20-m sprints (−0.08 ± 0.03 s and −0.04 ± 0.04 s) compared with CT (p < 0.05; d > 0.60). Standing long jump was significantly increased after ST when compared with CT (0.07 ± 0.04 m; p < 0.01; d = 0.88). Plyometric training showed higher improvements than ST in sprint (0.04 ± 0.03; p = 0.01; d = 0.71). It is suggested that 8 weeks of ST or PT seems to be effective to improve strength- and power-related variables in healthy untrained children. These could be considered as alternatives to traditional resistance training and be applied in school-based programs. [ABSTRACT FROM AUTHOR]

Recent data suggest that single-joint exercises are unnecessary to maximize the resistance training (RT) results in novice to advanced individuals. However, the present literature is still inconsistent on this topic and controversy arises. The aim of this study was to compare the effects of the unilateral dumbbell row (DR) (multiple-joint) vs. unilateral biceps curl (BC) (single-joint) exercises on strength and elbow flexors muscle thickness (MT). Ten untrained men were assigned to an 8-week RT program for elbow flexors, one arm performing DR and the other performing BC in a within-subject design. After a familiarization, pretraining MT was measured using an ultrasound (US) technique, and strength was tested using 10 repetition maximum (10RM) tests. After pretesting, 8 weeks of RT (4–6 sets, 8–12 repetitions to concentric failure, 2 sessions per week) was performed. Post-testing was conducted in the same order as pretesting 48 and 72 hours after the last session. Single-joint BC exercise resulted in higher hypertrophy of elbow flexors (11.06%) than the DR (5.16%) multijoint exercise after 8 weeks of RT (p50.009). The 10RM improvement was higher for DR in DR-trained arm, whereas 10RM for BC was higher in BC-trained arm. The single-joint exercise resulted in higher hypertrophy of the elbow flexors than multijoint exercise after 8 weeks of RT, whereas strength improvements were greater in accordance with specificity of RT exercise. Therefore, in RT prescription for elbow flexors hypertrophy, single-joint exercises such as BC should be emphasized. [ABSTRACT FROM AUTHOR]

Squat exercise variations are widely used and extensively researched. However, little information exists on the goblet squat (GBS) and landmine squat (LMS) and differences between men and women. This study investigated the differences in muscle activity and kinetics between the GBS and the LMS in 16 men and 16 women. Five repetitions of each squat type were performed loaded at 30% of their body mass. Vertical and anteroposterior ground reaction forces for the eccentric and concentric phases and peak vertical force were recorded with a force plate. Electromyographic (EMG) signals were recorded for the vastus medialis (VM), vastus lateralis (VL), semitendinosus (ST), and biceps femoris (BF). Normalized mean EMG values and ground reaction forces were analyzed with repeated measures analysis of variance (p < 0.05). Significant main effects for squat condition and sex were found. The LMS reduced activity in the quadriceps (VM and VL) muscles and vertical forces, while increasing posterior horizontal forces. In the LMS, men showed decreased ST activity, whereas women had decreased BF activity. Women exhibited greater quadriceps activity in both the GBS and LMS and greater ST in the LMS. Women also produced greater eccentric vertical force in both the GBS and LMS and less posterior horizontal forces in the LMS. The LMS may be useful to balance hamstring to quadriceps activity, increase horizontal loading, and reduce vertical loading. Conversely, the GBS can better target quadriceps activity and increase vertical loading. Sex differences should be considered for training programs that include the GBS and LMS. [ABSTRACT FROM AUTHOR]

Strength training history is an emerging academic area. The aim of the current study was to describe quantitively the history of inventions for strength training equipment. Content analysis was conducted of patent applications for strength training equipment filed with the U.S. Patent and Trademark Office before 1980. Applications were identified using relevant keyword searches in Google Patents. A total of 551 patent applications were analyzed. The earliest application identified was filed in 1860. Applications never exceed 6 per year until 1961 after which applications increased substantially, with a peak of 54 in 1979. Men invented 98.7% of all strength training devices. Lloyd J. Lambert, Jr. was the most prolific inventor, with 10 inventions. Types of inventions included mobile units (34.5%), stationary machines (27.9%), dumbbells (16%), racks or benches (8.0%), barbells (6.7%), and Indian clubs (3.8%). Common features included seats or benches (18.7%), cable-pulley systems (15.1%), weight stacks (8.2%), weight trays (4.5%), and cams (2.2%). Common types of resistance included weights or plates (33.2%), springs (11.6%), friction (9.1%), elastic bands (5.3%), and hydraulic (3.8%). Proposed invention benefits included adjustable resistance (37.4%), inexpensive (36.1%), simple to use (32.8%), compact design or easy storage (27.0%), multiple exercise options (26.1%), safety and comfort (25.4%), effectiveness (23.6%), portability (20.5%), adjustable size(15.8%), sturdiness or durability(15.8%), home use(13.6%),and light weight(13.6%). Certain aspects of strength training equipment have evolved over time. However, overall purposes and benefits of inventions have remained constant (e.g., affordability, convenience, personalization, safety, and effectiveness). [ABSTRACT FROM AUTHOR]

Godoy, DF, Cadore, EL, Feitosa, WG, Correia, RdA, and Castro, FAdS. Oxygen uptake of wave surfers and complementary parameters in front crawl and surfing-paddling tests. J Strength Cond Res 35(9): 2645-2650, 2021--The aim of this study was to assess the reliability of the oxygen uptake and complementary parameters (heart rate [HR], blood lactate concentration, and rate of perceived exertion [RPE]) obtained from surfers swimming and paddling in a swimming pool. Fourteen recreational male surfers (37.7 6 4.7 years old) were evaluated in (a) a maximal 300-m front crawl test and (b) paddling in a surfboard test, both at the same intensity and for the same duration. Peak oxygen uptake (V̇O2peak) during the tests (direct method), HR, blood lactate concentration (LA), and RPE were assessed. Two-way analysis of variance, a simple Student t test, effect size calculation, intraclass correlation coefficient, and limits of agreement were applied. In general, the tests presented similar results (except for HR), with low agreement, high intraclass correlation, and average to large effect sizes between swimming and paddling. The results suggest that surfers training in a swimming pool should not simply be swimming. Front crawl swimming and surf paddling are 2 distinct actions that should be practiced and tested on their own merits rather than assumed to be interchangeable. [ABSTRACT FROM AUTHOR]

Amateur Rugby Union has an inherent risk of injury that is associated with detrimental effects on player welfare and team performance. Training load (TL) is a modifiable risk factor that, when monitored, may provide strength and conditioning (S&C) coaches with opportunities to reduce the risk of injury. The purpose of this study was to explore TL monitoring practices used by S&C coaches working with male and female amateur adult Rugby Union teams and their rationale for using such. Thirty-three (n = 31 male and n = 2 female) S&C coaches representing 62% of the total number of male clubs and 71% of female clubs, playing at the highest national amateur level, participated in the study by completing an online survey. Seventy-three percent of respondents stated that they monitor TL. The most common method of recording TL was the session rating of perceived exertion (sRPE), used in 83% of monitoring systems. Thirty-three percent of the S&C coaches surveyed use the sRPE data to calculate the acute:chronic workload ratio (ACWR) for highlighting when players are at risk of injury. This study is the first of its kind to exclusively examine the TL monitoring practices of S&C coaches working with amateur adult Rugby Union teams. Thirteen S&C coaches responded to the open-ended question and 3 higher order themes were highlighted: (a) communication with players (b) support from other staff and (c) limiting factors. [ABSTRACT FROM AUTHOR]

Limited scholarship exists on the history of strength training research. The current review advances existing qualitative and biographical work by inventorying all experimental studies and case reports published before 1980 on the effects of $1 week of strength training on human health and function. Data on authors, journals, citations, study samples, training interventions, study outcomes, and study themes were extracted and summarized. Three hundred thirty-nine strength training studies were published between 1894 and 1979. Studies included 14,575 subjects, with 10,350 undergoing strength training. Subjects were usually healthy (81.1% of articles), university students (51.0%), or aged 18-65 years (86.7%). Men comprised 70.0% of subjects. Interventions typically involved isoinertial only (64.6%) or isometric only (35.4%) training. Upper-body interventionsweremore common (35.4%) than lower-body interventions (27.4%). Duration and frequency of trainingwere typically 4-8 weeks (55.3%) and 3 days per week (39.2%), respectively. Isometric maximal voluntary contractions (54.0%) and one repetition maximum (20.4%) were the most common muscle strength tests. Other common outcomes included limb girths (20.9%) andmuscle endurance (19.5%). Common research themes were physiology (54.3%), physical fitness (28.9%), and injury/rehabilitation (20.4%). The 339 studies have been cited 21,996 times. Moritani and deVries' 1979 article on time course of neuromuscular adaptations is the most highly cited (1,815 citations). DeLorme (5 articles and 772 citations), Hellebrandt (4 articles and 402 citations), Rasch (9 articles and 318 citations), and Berger (12 articles and 1,293 citations) made the largest contributions. Research Quarterly published the most articles (27.4%). The history of strength training research is discussed in the context of the results. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare strength, muscle activation, and bar velocity between the traditional (TRAD) and safety squat bar (SSB) back squat. Thirty-two men (21.9463.1 years, 1.7860.8 m, 81.7610.1 kg) volunteered to complete this randomized, crossoverdesign study. Subjects completed 2 separate 1 repetition maximum (1RM) sessions using either the TRAD or SSB. Subsequently, subjects completed 1 session of 3 repetitions at 65 and 85% of their 1RM for each squat condition (SSB & TRAD). Peak muscle activation of 7 muscles from the lower body and trunk was recorded through surface electromyography (EMG), and mean velocity (MV) was recorded by a linear transducer. Electromyography and MV were analyzed by a 2 3 2 (bar 3 load) repeated-measures analysis of variance. A Pearson correlation was used to determine the relationship of 1RM load between bars. Squat 1RM was significantly higher (p, 0.001; 11.6%) for TRAD (144.7 kg) compared with SSB (128.8 kg), and a strong correlation (r 5 0.94) was observed between 1RM values of each bar. A significant main effect was seen in EMG (p, 0.001) and MV for load (p, 0.001). No significant bar 3 load interaction was observed between conditions for any EMG or bar velocity measure (p . 0.05). The SSB produces similar muscle activation and bar velocities compared with the TRAD at relative intensities. However, absolute loads should be adjusted when changing squat bars during a training cycle. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the acute effects of Fat Gripz (FG) on muscular activation and strength. Resistance trained men (n = 15; age = 22.4 6 2.3 years; mass = 83.2 6 11.1 kg) performed 2 experimental trials in a randomized order. Subjects completed 1 repetition maximum (1RM) testing with an Olympic barbell (OB) and with FG attached to an OB during the exercises of deadlift, bent-over row, upright row, concentration curl, and completed maximum repetitions of pull-ups until failure. Surface electromyography (EMG) was used to measure muscle activity from 8 upper extremity muscles (trapezius, medial deltoid, biceps brachii, triceps brachii, flexor carpi radialis, flexor carpi ulnaris, extensor carpi radialis, and extensor carpi ulnaris), while performing maximal voluntary isometric contractions during 1RM trials and while performing maximum number of pull-ups. When using the FG, 1RM strength was significantly decreased for each exercise, and the maximal number of pull-ups completed was significantly lower. Electromyography muscle activity was significantly increased in the forearm and shoulder muscles, but significantly decreased in the upper arm muscles with the use of FG during deadlift, bent-over row, and pull-ups. However, there were no differences for EMG activity for upright row and concentration curl. Differences in maximal strength, pull-up performance, and EMG activity with FG use may be due to the different muscle length positions. Although FG training may increase neuromuscular activation, decrements in muscular strength may result in prescribing low training loads that may not be ideal for building muscular strength. [ABSTRACT FROM AUTHOR]

This study investigated the acute effects of battle rope (BR) exercise on basketball players' performance, blood lactate levels, rating of perceived exertion (RPE), and perceived muscle soreness. Fifteen well-trained Division-I male basketball players underwent the same test procedure at baseline, before BR exercise (30 minutes of rest after the baseline test), and after BR exercise. The 30-minute experimental protocol comprised 6 BR exercises at a work-to-rest ratio of 1:2 (20-second exercise and 40-second rest). Shooting accuracy, basketball chest pass speed, countermovement jump (CMJ) height, blood lactate levels, RPE (Borg Category-Ratio-10 scale), and perceived muscle soreness (visual analog scale, 0-100 mm) were measured in each test. The results indicated no change for any variables between baseline and before BR exercise. After BR exercise, performance decrements (p < 0.05) were recorded in shooting accuracy (16.9%) and basketball chest pass speed (9.1%), but no significant changes were observed for CMJ height. Battle rope exercise caused increases in blood lactate levels (13.6 mmol⋅L-1), RPE (9.9), and perceived muscle soreness (upper-limb: 63-67 mm; trunk: 43-68 mm; and lower-limb: 45-52 mm). In conclusion, BR exercise is physically demanding on the upper body, resulting in decreased performance in shooting accuracy and basketball chest pass speed. Battle rope exercise may not be beneficial before a practice or game because it triggers acute exercise-induced performance decrements and fatigue. However, BR exercise may be suitable for basketball training sessions in which the objective is to strengthen technical skills under fatiguing conditions. [ABSTRACT FROM AUTHOR]

Currently, it is widely accepted that adopting a long rest period (3-5 minutes) during maximal strength and power exercise is of importance in reducing acute fatigue and maintaining power and technique proficiency. However, despite the fact that weightlifting is an example of maximal strength exercise, only 2 minutes are officially allowed when athletes attempt 2 successive lifts. The purpose of this study was to compare 3- vs. 2-minute intermaximal repetition rest periods (IMRRPs) on performance, rate of perceived exertion (RPE), technical efficiency, and power production during 2 successive maximal repetitions of clean & jerk (C&J). Nine elite weightlifters (age: 24.4 ± 3.6 years, body mass: 77.2 ± 7.1 kg, height 176.0 ± 6.4 cm, and 1 repetition maximum C&J: 170.0 ± 5.0 kg) performed 2 separate testing sessions using 2-minute IMRRP (IMRRP-2) and 3-minute IMRRP (IMRRP-3), in a randomized order, while barbell kinematics and kinetics were recorded. Results showed that the longer IMRRP-3 minutes led to the maintenance of clean technique (from the first to the second repetition) evidenced by a 1.86% lower decline in peak vertical displacement (p = 0.03) and attenuation of increased peak horizontal displacements with a 1.74% (p = 0.03) less backward movement during the first pull, a 3.89% (p = 0.008) less forward movement during the second pull, and a 4.7% (p = 0.005) less backward movement during the catch phase. In addition, attenuation of peak velocity (2.22%; p = 0.02), peak vertical ground reaction force (1.70%; p = 0.03), and peak power (2.14%; p = 0.02) declines were shown using IMRRP-3 compared with IMRRP-2. Increasing IMRRP from 2 to 3 minutes was also shown to decrease RPE values (8.02%; p = 0.008) and to enhance supramaximal C&J performance (1.55%; p = 0.003). The results of this study suggest 3 minutes to be the most advantageous IMRRP in terms of maintaining technical efficiency, power output, reducing fatigue perception, and enhancing performance in elite weightlifters. [ABSTRACT FROM AUTHOR]

We tested whether exercising with a stronger simulated (i.e., software-generated) partner leads to greater work effort compared to exercising alone, to help those seeking to maintain or improve fitness levels with long-term high-intensity training, but who find it necessary or practical to exercise in social isolation. Forty-one middle-aged adults, who participated in at least 30 minutes of vigorous exercise 3x⋅wk-1, trained on a cycle ergometer 6 days per week for 24 weeks in an alternating regimen of moderate-intensity 30-minute continuous and 3 types of high-intensity interval sessions (8 x 30-second sprints, 6 x 2-minute ladders, and 4 x 4-minute intervals). They were assigned either no partner (control), an always superior partner, or a not always superior partner. Participants varied cycle power output to increase or decrease session intensity during the repeated moderate-intensity sessions (30-minute continuous) and 1 of the 3 high-intensity sessions (4 x 4-minute intervals). Changes in intensity were used as a measure of effort motivation over time. Nested multilevel models of effort trajectory were developed and alpha was set to 0.05. For continuous and interval sessions, effort trajectory was positive and significant for those with an always superior partner, but not significantly different from control. Within interval sessions, those with an always superior partner significantly increased effort in the fourth interval compared to control (p = 0.02). Exercising with an always superior partner leads to greater work efforts during the hardest interval training compared to exercising alone. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the changes in gastrocnemius muscle thickness (MT) between conditions such as which foot was pointed outward (FPO), foot was pointed inward (FPI), or foot was pointed forward (FPF). Twenty-two young men (23 ± 4 years) were selected and performed a whole-body resistance training program 3 times per week for 9 weeks, with differences in the exercise specific for calves. The calf-raise exercise was performed unilaterally, in a pin-loaded seated horizontal leg-press machine, in 3 sets of 20-25 repetitions for training weeks 1-3 and 4 sets for weeks 4-9. Each subject's leg was randomly assigned for 1 of the 3 groups according to the foot position: FPO, FPI, and FPF. Measurements with a B-mode ultrasound were performed to assess changes in MT of medial and lateral gastrocnemius heads. After the training period, there were observed increases in MT of both medial (FPO = 8.4%, FPI = 3.8%, and FPF = 5.8%) and lateral (FPO 5 5.5%, FPI = 9.1%, and FPF = 6.4%) gastrocnemius heads, and significant differences for magnitude of the gains were observed between FPO and FPI conditions (p < 0.05). Positioning FPO potentiated the increases in MT of the medial gastrocnemius head, whereas FPI provided greater gains for the lateral gastrocnemius head. Our results suggest that head-specific muscle hypertrophy may be obtained selectively for gastrocnemius after 9 weeks of calf training in young male adults. [ABSTRACT FROM AUTHOR]

Tavares, VDdO, Agricola, PMD, Nascimento, PHD, Oliveira Neto, L, Elsangedy, HM, and Machado, DGS. The effect of resistance exercise movement tempo on psychophysiological responses in novice men. J Strength Cond Res 34(5): 1264-1273, 2020 This study aimed to compare the effects of movement tempo in resistance exercise (RE) on psychophysiological responses in novice men. Seventeen novice men (24.5 ± 3.2 years; 79.3 ± 8.22 kg; 1.76 ± 0.06 m) performed the 10 repetition maximum (10RM) test for bench press and knee extension in 2 sessions (test-retest) and 2 RE training sessions with different movement tempos in a random and counterbalanced order (4 sets of 10 repetitions). The low tempo RE (LTRE) session was performed using 50% 10RM with 3-0-3-0 seconds (concentric, pause, eccentric, and pause, respectively). The moderate tempo RE (MTRE) session was performed using 80% 10RM with 1-0-1-0 seconds (concentric, pause, eccentric, and pause, respectively). Affective valence (Feeling Scale), perceived activation (FAS), attentional focus, and ratings of perceived exertion (Borg 6-20) were reported after each set. A two-way analysis of variance with repeated measures showed only a significant main effect of the set (all ps>0.05), indicating changes between sets but not between LTRE and MTRE. In addition, a paired-samples t-test did not find significant differences between LTRE and MTRE, on average, in any psychophysiological responses (all ps > 0.16). Thus, for the protocol tested, there is no psychophysiological advantage to using either LTRE or MTRE in novice men. From a practical perspective, for psychophysiological responses, the present results suggest that it is up to the trainer∕coach to decide which RE movement tempo to use, which will depend on the purpose of the training period, specificity, client tolerance of and preference for exercise intensity, and movement tempo. [ABSTRACT FROM AUTHOR]

GÓmez-Carmona, CD, Bastida-Castillo, A, Rojas-Valverde, D, de la Cruz Sánchez, E, Garcia-Rubio, J, Ibáñez, SJ, and Pino-Ortega, J. Lower-limb dynamics of muscle oxygen saturation during the back-squat exercise: effects of training load and effort level. J Strength Cond Res 34(5): 1227-1236, 2020 The aim of this study was to analyze the effect of strength training on lower limb muscle oxygenation. The sample consisted of 12 male subjects (22.4 ± 1.73 years; 1.81 ± 0.08 cm height and 77.76 ± 8.77 kg body mass). Six different strength training stimuli were analyzed, based on the training variables: load (60-75% 1 repetition maximum [1RM]) and level of effort (LE) (E1: 4 × 8 [20RM], E2: 4 × 12 [20RM], E3: 4 × 16 [20RM], E4: 4 × 4 [10RM], E5: 4 × 6 [10RM], and E6: 4 × 8 [10RM]) in the squat exercise up to 90° with a 2-second stop between repetitions to avoid the myotatic reflex. Oxygen saturation at the beginning of the series (SmO2start), oxygen saturation at the end of the series (SmO2stop), percentage of oxygen saturation loss (▿ %SmO2), and reoxygenation time (SmO2recT) were assessed using a near-infrared spectroscopy device. In addition, the percentage of mean propulsive velocity loss (%MPVL) was recorded using a linear transducer. The results suggested an influence of LE and training load on muscle oxygenation. A greater LE was directly associated with SmO2recT (r =0.864), ▿ %SmO2 (r=0.873), and %MPVL (r=0.883) and inversely with SmO2stop (r =−0.871). When the same LE was used (E1 vs. E4, E2 vs. E5, and E3 vs. E6), it was found that the stimuli with a higher load had a lower SmO2recT, ▿ %SmO2, and %MPVL and a higher SmO2stop. Muscle oxygen saturation was found to be minimal (%SmO2 =0) in stimuli with a LE greater than 60% (E3 and E6). The SmO2 variables studied in the present research could be considered as an easier and more useful method for understanding skeletal muscle fatigue during resistance training [ABSTRACT FROM AUTHOR]

Although forms of integrative neuromuscular training (INT) are used extensively for injury prevention and treatment, no information exists about its effects on performance of adolescent athletes. We investigated the effects of an in-season INT intervention on performance of early-adolescent players using a 2-group, repeated-measures design. Twenty-eight early adolescents were randomly assigned to a control group (CG, participated only in soccer training, N = 14, 11.4 ± 0.57 years, Tanner stage 2.8 ± 0.6) or an experimental group (INT was added to conventional soccer training, N = 14, 11.2 ± 0.5 years, Tanner stage 2.6 ± 0.5). Integrative neuromuscular training (8 weeks, 3 sessions wk−1) aimed to develop core strength, hamstrings eccentric strength, hip∕knee musculature, and dynamic stability using body mass exercises, medicine balls, rocker boards, Bosu, stability balls, etc. Ball shooting speed, speed (10, 20-m), change of direction (COD), jumping performance, and strength were measured before and after training. A 2-way repeated-measures ANOVA was used to analyze data. Integrative neuromuscular training improved 10- and 20-m speed (2.52-2.13 and 3.61-3.39 seconds, respectively, p < 0.05), strength (40.1-44.4 kg, p < 0.05), jumping ability (squat jump: 16.3-17.9 cm; countermovement jump: 19.1- 20.3 cm, p < 0.05), COD (18.0-17.3 seconds, p < 0.05), and shooting speed (73.8-79.0 km h−1, p < 0.05). In the CG, soccer training caused an improvement of smaller magnitude in 10 m and shooting speed (p < 0.05), whereas COD and jumping performance remained unaffected while 20-m speed, COD, and strength deteriorated. These results indicate that an 8-week INT program may induce positive adaptations in performance of early-adolescent soccer players during in-season training, suggesting that INT may be an effective training intervention for this age group. [ABSTRACT FROM AUTHOR]

Training that is efficient and effective is of great importance to an athlete. One method of improving efficiency is by incorporating supersets into resistance training routines. However, the structuring of supersets is still unexplored. Therefore, the purpose of this study was to assess the effects of agonist-antagonist (A-A), alternate peripheral (A-P), and similar biomechanical (SB) superset configurations on rate of perceived exertion (RPE), kinetic and kinematic changes during the bench press. Ten subjects performed resistance training protocols in a randomized-crossover design, with magnitude-based inferences assessing changes/differences within and between protocols. Changes in rate of perceived exertion were very likely and almost certainly greater in the A-P and SB protocols when compared with the A-A, whereas all superset protocols had very likely to almost certain reductions in mean velocity and power from baseline. Reductions in mean velocity and power were almost certainly greater in the SB protocol, with differences between the A-A and A-P protocols being unclear. Decreases in peak force were likely and almost certain in the A-A and SB protocols respectively, with changes in A-P being unclear. Differences between these protocols showed likely greater decreases in SB peak forces when compared to A-A, with all other superset comparisons being unclear. This study demonstrates the importance of exercise selection when incorporating supersets into a training routine. It is suggested that the practitioner uses A-A supersets when aiming to improve training efficiency and minimize reductions in kinetic and kinematic output of the agonist musculature while completing the barbell bench press. [ABSTRACT FROM AUTHOR]

Different training devices are available to trigger greater activation of the abdominal muscles compared with that achieved during traditional abdominal exercises. This study aimed to compare the electromyographic (EMG) activity of the upper and lower rectus abdominis, external oblique abdominis, erector spinae, and rectus femoris (RF) muscles during traditional crunch and exercise using the 5-minute Shaper device. A convenience sample of 15 healthy men (mean ± SD; age: 23.65 ± 4.49 years, body fat percentage: 14.26 ± 3.56%) was selected. All men regularly participated in physical activity. Electromyographic data were collected for 5 repetitions of each abdominal exercise (traditional crunch and exercise using the 5-minute Shaper device at beginner, intermediate, advanced, and extreme levels) in a randomized and counterbalanced manner. Data were collected using simple differential surface electrodes and analyzed using repeated-measures analysis of variance (p < 0.05). Electromyographic signals were quantified using a root-mean-square analysis and normalized using the maximum voluntary isometric contraction. Traditional crunch produced greater or similar EMG activity in the abdominal muscles and minimized RF activity compared to the 5-minute Shaper device, hence, traditional crunch is preferred for training, especially for individuals with weak abdominal musculature and lower back problems. Therefore, the use of the 5-minute Shaper device may be questioned when it is intended to intensify the activity of the abdominal muscles; however, this apparatus may be used if greater variations in training are desired, depending on individual preferences. [ABSTRACT FROM AUTHOR]

Neuroplastic changes in the primary motor cortex accompany performance improvements following motor practice. Recent evidence suggests that the corticospinal responses to strength and skill training are similar, following both a single session and repeated bouts of training, promoting discussion that strength training is a form of motor learning. However, these findings are limited by the lack of a light-load strength training group. Therefore, the aim of the current study was to determine whether a single session of heavy-load strength training, light-load strength training or skill training differentially modulates the corticospinal pathway. Transcranial magnetic stimulation was used to assess the excitatory and inhibitory circuitry of the motor cortex following a single session of skill training, and following a single session of light-load and heavy-load strength training. Following a single session of training, participants in all groups experienced comparable increases in corticospinal excitability (ranging from 38 to 46%, all p < 0.05); however, disparity was observed in the inhibitory responses. Corticospinal inhibition was reduced in all 3 single-sessions, although to a greater magnitude in the heavy-load and skill-training sessions (22 and 18% respectively, compared with 11% following light-load training, all p < 0.05). Short-interval intracortical inhibition was reduced immediately following single sessions of heavy-load strength training (40% p < 0.05) and skill training (47% p < 0.05), but remained unchanged the following light-load strength training session. It appears that the corticospinal responses to single sessions of different types of strength and skill training are task-dependent. These findings reinforce the notion that strength training, at least when heavily-loaded, can be considered a form of motor learning, potentially because of the sensory feedback involved. [ABSTRACT FROM AUTHOR]

This meta-analysis characterized female youths' adaptability to plyometric training (PT). A second objective was to highlight the limitations of the body of literature with a view to informing future research. Fourteen studies were included in the final analysis. The effect size (ES = Hedges' g) for the main effect of vertical jump performance was "small" (ES = 0.57, 95% confidence interval: 0.21-0.93). Effect sizes were larger in younger (<15 years; ES = 0.78 [0.25-1.30] vs. 0.31 [-0.18 to 0.80]), shorter (<163 cm; ES = 1.03 [0.38-1.68] vs. 0.25 [-0.20 to 0.70]), and lighter (<54 kg; ES = 1.14 [0.39-1.89] vs. 0.26 [-0.15 to 0.67]) participants. Programming variables seemed to influence adaptive responses with larger effects in interventions which were longer (8 weeks; ES = 1.04 [0.35-1.72] vs. 0.24 [-0.11 to 0.59]), had greater weekly training frequency (>2; ES = 1.22 [0.18-2.25] vs. 0.37 [0.02-0.71]), and whose sessions were of longer duration (≥30 minutes ES = 1.16 [0.14-2.17] vs. 0.33 [0.03-0.63]). More than 16 sessions per program (0.85 [0.18-1.51]) was more effective than exactly 16 sessions (0.46 [0.08-0.84]) which, in turn, was more effective than less than 16 (0.37 [-0.44 to 1.17]). These findings can inform the prescription of PT in female youth. [ABSTRACT FROM AUTHOR]

Reduction of physiological strain under a hot and humid environment by a hybrid cooling vest. J Strength Cond Res 33(5): 1429-1436, 2019-Cooling treatment is regarded as one of good practices to provide safe training conditions to athletic trainers in the hot environment. The present study aimed to investigate whether wearing a commercial lightweight and portable hybrid cooling vest that combines air ventilation fans with frozen gel packs was an effective means to reduce participants' body heat strain. In this within-subject repeated measures study, 10 male volunteers participated in 2 heatstress trials (one with the cooling vest-COOL condition, and another without-CON condition, in a randomized order) inside a climatic chamber with a controlled ambient temperature 33° C and relative humidity (RH) 75% on an experimental day. Each trial included a progressively incremental running test, followed by a 40-minute postexercise recovery. Core temperature (Tc), heart rate (HR), sweat rate (SR), rating of perceived exertion (RPE), exercise duration, running distance, and power output were measured. When comparing the 2 conditions, a nonstatistically significant moderate cooling effect in rate of increase in Tc (0.03 ± 0.02° C m ir r 1 for COOL vs. 0.04 ± 0.02° C -m ir r1 for CON, p = 0.054, d = 0.57), HR (3 ± 1 b-min~1 -miru1 for COOL vs. 4 ± 1 b min-1 -m ir r1 for CON, p = 0.229, d = 0.40), and physiological strain index (PSI) (0.20 ± 0.06 unit-min-1 for COOL vs. 0.23 ± 0.06 unit-min-1 for CON, p = 0.072, d = 0.50) was found in the COOL condition during exercise. A nonstatistically significant (p > 0.05) trivial cooling effect {d < 0.2) was observed between the COOL and CON conditions for measures of exercise duration, running distance, power output, SR, and RPE. It is concluded that the use of the hybrid cooling vest achieved a moderate cooling effect in lowering the rate of increase in physiological strain without impeding the performance of progressively incremental exercise in the heat. [ABSTRACT FROM AUTHOR]

Previously, perceived exertion in submaximal resistance exercise protocols was reported to be affected by the intensity of load followed by work-to-rest ratio. Nevertheless, the effect of set configuration, which entails the metabolic, hormonal, and neuromuscular implication of the session, is currently unknown, despite the fact that perceived exertion discriminates these differences. We aimed to analyze the effect of 3 submaximal set configurations on perceived exertion and their relationship with velocity as a mechanical measure of fatigue. Seventeen healthy subjects (23 ± 2 years) performed with the 10-repetition maximum load on the leg press (211 ±45 kg) a total of 40 repetitions with 720 seconds of rest in 3 randomized experimental sessions with the same work-to-rest ratio. The sessions consisted of an interrepetition rest design performing individual repetitions, a cluster design performing groups of 4 repetitions, and a traditional design performing groups of 8 repetitions. At the end of the session, the nonparametric analysis of variance-type test revealed differences between protocols (p < 0.001), with lower values of perceived exertion in the interrepetition rest design in comparison with the cluster design (p = 0.003) and traditional design (p < 0.001). In addition, Spearman's rank correlations (p < 0.001) were observed for the interrepetition rest design (rho = -0.72) and traditional design (rho = -0.8) between perceived exertion and velocity. Our findings suggest that the submaximal set configuration is a determinant of perceived exertion by itself, and that perceived exertion represents similar mechanisms as velocity, such as fatigue and certain characteristics of the session and the individual. [ABSTRACT FROM AUTHOR]

Lima, C, Li, Y, Low, JL, Herat, N, and Behm, DG. Superior training-specific adaptations with an 8-week yoak push-up training program. J Strength Cond Res 32(9): 2409–2418, 2018—There are few progressive metastability training programs in the literature. The purpose of this study was to investigate changes in strength, endurance, muscle activation, and neuromuscular efficiency after an 8-week progressive, push-up training program under stable and unstable conditions. Nineteen male and female recreationally trained participants performed twice per week, an 8-week push-up training program, using either a relatively unstable suspension system (Yoak) or under stable conditions. Participants were tested in 2 separate sessions before and after training for chest press maximal voluntary isometric contraction (MVIC) forces, and unstable and stable push-up endurance. Participants were tested during all testing measures for anterior deltoid, biceps brachii (BB), triceps brachii (TB), and serratus anterior (SA) electromyography (EMG) activity. The training progression consisted of altering the suspension configurations, push-up height, and increasing the number of sets (1–3 sets). The stable group performed 153.3 and 33.8% less repetitions than the Yoak group when performing push-ups on the Yoak device or stable floor, respectively (p = 0.03). Training-induced MVIC forces were 9.2% (p = 0.03) greater for the Yoak vs. the stable group. Regarding neuromuscular efficiency, the Yoak group decreased (30.4%; p = 0.01) and stable group increased (97.8%; p = 0.02) antagonist BB EMG activity from pre- to post-training. Both groups decreased the TB fatigue index from pre- to post-training. Nevertheless, Yoak group demonstrated 12.5% (p = 0.09) and 8.9% (p = 0.02) lower fatigue indexes with TB and SA, respectively, than the stable group. These findings suggest that Yoak training demonstrates superior improvements over stable training for push-up endurance, neuromuscular efficiency, MVIC, and fatigue index. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the perceptual responses to resistance exercise with heavy loads (80% 1 repetition maximum [1RM]), light loads (20% 1RM), or light loads in combination with blood flow restriction (BFR). Despite the use of light loads, it has been suggested that the adoption of BFR resistance exercise may be limited because of increases in delayed onset muscle soreness (DOMS) and perceived exertion. Seventeen healthy untrained males participated in this balanced, randomized cross-over study. After 4 sets of elbow-flexion exercise, participants reported ratings of perceived exertion (RPE), with DOMS also recorded for 7 days after each trial. Delayed onset muscle soreness was significantly greater for low-pressure continuous BFR (until 48 hours postexercise) and high-pressure intermittent BFR (until 72 hours postexercise) than for traditional heavy-load resistance exercise and light-load resistance exercise. In addition, RPE was higher for heavy-load resistance exercise and high-pressure intermittent BFR than for low-pressure continuous BFR, with all trials greater than light-load resistance exercise. For practitioners working with untrained participants, this study provides evidence to suggest that to minimize the perception of effort and postexercise muscle soreness associated with BFR resistance exercise, continuous low-pressure application may be more preferential than intermittent high-pressure application. Importantly, these perceptual responses are relatively short-lived (~2 days) and have previously been shown to subside after a few exercise sessions. Combined with smaller initial training volumes (set x repetitions), this may limit RPE and DOMS to strengthen uptake and adherence and assist in program progression for muscle hypertrophy and gains in strength. [ABSTRACT FROM AUTHOR]

Recently, an interest has developed in the potential to rinse the oral cavity with key nutrients to impact various types of exercise and presumably sporting performance. Although multiple studies examining carbohydrate mouth rinsing have been completed, conflicting evidence surrounding caffeine mouth rinsing persists, and no research has explored its ability to impact high-intensity, intermittent running performance. This study investigated the independent and synergistic ability of carbohydrate and caffeine mouth rinsing to improve intermittent running performance. The Yo-Yo Intermittent Recovery Test-Level 1 (Yo-Yo Level 1) was completed in 10 collegiate (National Collegiate Athletic Association [NCAA] Division II) male lacrosse players after a 10-second mouth rinse with a solution of either carbohydrate (CHO), caffeine (CAF), carbohydrate + caffeine (CHO + CAF), placebo (H2O), or a no rinse control (CON). No significant improvements in Yo-Yo IRT-1 performance were found (p > 0.05). Perceptual indications of effort (i.e., rating of their perceived exertion [RPE]) were significantly lower (p ≤ 0.05) in CHO and CHO + CAF when compared with CON after speed level 11. Interestingly, RPE levels were nonsignificantly lower in all but one level of the Yo-Yo Level 1 for CHO in comparison with other groups. Carbohydrate and caffeine mouth rinsing seems to exert no impact on running performance before maximal intermittent running in a group of male collegiate lacrosse players. [ABSTRACT FROM AUTHOR]

This study examines the influence ambient temperature has on the distances covered by players in soccer matches. For this purpose, 1,211 games from the top German professional leagues were analyzed over the course of the seasons 2011/12 and 2012/13 using an optical tracking system. Data show (a) significant differences in the total distance covered (TDC, in meters per 10 minutes) between the 1. Bundesliga (M = 1,225) and 2. Bundesliga (M = 1,201) and (b) a significant decrease in TDC from neutral (-4 to 13° C, M = 1,229) to warm (≥14° C, M = 1,217) environments. The size of the temperature effect is greater in the 1. Bundesliga (d = 0.30 vs. d = 0.16), although these players presumably have a higher level of fitness. This suggests that better players reduce their exertion level to a greater extent, thus preserving their ability to undertake the high-intensity activities when called upon. No reduction in running performance due to cold (≤5° C) temperatures was observed. [ABSTRACT FROM AUTHOR]

The current study examined how the impact of pitch dimensions influences physiological and running performance during 4-minute small-sided games (SSGs). Twenty-four (n = 24) hurling players were monitored with global positioning system and heart rate monitors during the in-season training period. Total distance (in meters), high-speed running distance (in meters) (≥17 km⋅h-1), very high-speed running distance (≥22 km⋅h-1) (in meters), total accelerations (n), acceleration distance (in meters), and peak and mean velocity (in kilometers per hour) were calculated. Additionally, SSGs rate of perceived exertion (RPESSG; AU), % maximum heart rate, and individualized training impulse (iTRIMP; AU) were collected. The current results show that the manipulation of SSGs pitch size has an impact on the running performance and physiological responses. The data showed that SSGs played on large pitches (SSG80 x 20 m) had greater running demands than medium (SSG60 x 20 m) or small (SSG40 x 20 m) pitches, with significantly more distance covered in all movement categories. Total distance covered at high speed was 354 ± 111 m on a large pitch, 254 ± 72 m on a medium pitch, and 198 ± 62 m on a small pitch. Large pitch dimensions resulted in greater physiological and perceptual demands on players (higher %HRmax, iTRIMP [AU], and RPESSG [AU]) compared with medium and small pitches. The current data help applied practitioners to understand further how modifying different aspects of SSGs can alter the running and physiological responses of players. Moreover, applied practitioners now have consistent information to design and optimize their training time in mixing the physical, technical, and tactical elements within specific SSGs pitch dimensions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the acute physiological responses within and between resistance training (RT) and high-intensity interval training (HIIT) matched for time and with comparable effort, in a school setting. Seventeen early adolescents (12.9 ± 0.3 years) performed both RT (2-5 repetitions perceived short of failure at the end of each set) and HIIT (90% of age-predicted maximum heart rate), equated for total work set and recovery period durations comprising of 12 "sets" of 30-second work followed by 30-second recovery (total session time 1 2 minutes). Variables of interest included oxygen consumption, set and session heart rate (HR), and rate of perceived exertion, and change in salivary cortisol (SC), salivary alpha amylase, and blood lactate (BL) from presession to postsession. Analyses were conducted to determine responses within and between the 2 different protocols. For both RT and HIIT, there were very large increases pretrial to posttrial for SC and BL, and only BL increased greater in HIIT (9.1 ± 2.6 mmol⋅L-1) than RT (6.8 ± 3.3 mmol⋅L-1). Mean set HR for both RT (170 ± 9.1 b⋅min-1) and HIIT (1 79 ± 5.6 b⋅min-1) was at least 85% of HRmax. ...O2 over all 12 sets was greater for HIIT (33.8 ± 5.21 ml⋅kg-1⋅min-1) than RT (24.9 ± 3.23 ml⋅kg-1⋅min-1). Brief, repetitive, intermittent forays into high but not supramaximal intensity exercise using RT or HIIT seemed to be a potent physiological stimulus in adolescents. [ABSTRACT FROM AUTHOR]

The National Strength and Conditioning Association (NSCA) formed in 1978 when a group of 76 strength and conditioning coaches banded together to start an organization whose goal was to facilitate the exchange of ideas on strength training for sports. At the time, very little research existed regarding strength training protocols or their effects. Members clamored for scientific information, however, and by the group's second meeting, they moved to establish a research committee and a professional journal. In the years that followed, more members with experience both as practitioners of strength coaching and training and as scientists joined the organization. As membership demographics shifted, the NSCA's mission changed from exchanging ideas about strength training to creating research on its effects. The group sought to "bridge the gap" between scientists and practitioners, and to that end, the NSCA Journal published features like the "Sport Performance Series" and "Roundtable" articles containing applied science and investigations of claims made by strength equipment manufacturers about the efficacy of their products. In 1987, a second journal, The Journal of Applied Sport Science Research, was established to provide more access to research-based publications, now renamed the Journal of Strength and Conditioning Research. With over 400 articles published in the JSCR in 2014 alone, the science of strength has advanced dramatically since the NSCA's founding. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the effects of various dosages of light-emitting diode therapy (LEDT) on muscle fatigue while performing a single-leg extension to exhaustion. A total of 34 recreationally resistance-trained athletes between the ages of 18 and 26 participated in 4 trials. Each trial included pre-exercise/postexercise blood lactate measurements and 2 sets of 3 maximal voluntary isometric contractions (MVICs), followed by LEDT on 6 points across the superficial quadriceps. Each randomized trial consisted of a placebo, 30, 60, or 120 seconds on each point on the quadriceps. Three minutes after LEDT, the participants performed an eccentric leg extension with 120% of MVIC until fatigue. There was significant increase in the number of repetitions performed between the placebo treatment and 60 seconds (p = 0.023), as well as placebo and 120 seconds (p = 0.004) of irradiation on each point. There were no significant differences in blood lactate levels between any of the 4 trials. In conclusion, LEDT had a positive effect on performance when irradiating 6 points on the superficial quadriceps for 60 and 120 seconds before an eccentric leg extension. [ABSTRACT FROM AUTHOR]

It is well established that many physiological functions are time-of-day (TOD) dependent, and their circadian rhythms are well documented in healthy populations at resting state. In fact, greater rate of oxidative stress, white blood cell, homocysteine, and muscle damage markers were shown in the early evening (≈ 18:00 hours), and more efficient antioxidant activity was observed in the early morning (≈ 06:00 hours). During physical tasks, the majority of the above-mentioned physiological functions increase from pre to post physical exercise with different rates of increases from morning to evening. These different rates of increases are suggested to alter the physiological resting diurnal variation. In this context, given the possible significant interaction "TOD x physical exercise," circadian rhythms of the physiological responses during physical activity are still not well established in trained subjects. Otherwise, it was suggested that the diurnal variation of these biochemical parameters could, in part, explain the typical diurnal fluctuation of physical performance. Therefore, the aim of this review was to summarize the currently available studies investigating the circadian rhythms of physiological functions at rest and after physical exercise and to establish their possible effect on the diurnal variation of sport performance. Although studies in this field are limited, the available information shows that compared with sedentary subjects, trained population maintained similar diurnal variations of hematological parameters, homocysteine, and some biochemical markers at rest and even after physical exercise. However, after strength exercises, the circadian rhythms for the majority of oxidative stress and muscle damage markers were altered because of the higher rate of increased pre-post exercises registered in the morning compared with the afternoon and evening. The available studies reveal that the significant circadian variation observed for sport performances could be more likely explained by the alteration of ionic movement and the diurnal fluctuation of homocysteine, lactate, muscle damage, and antioxidant markers. [ABSTRACT FROM AUTHOR]

The article presents abstracts on sports physiology which include effects of taekwondo training on metabolism and aerobic capacity, performance testing of women volleyball players, and effects of stretching on jump performance of young basketball players.

Little research has been done examining the most physically demanding tasks a SWAT officer may perform in the line of duty. Our objective was to analyze the rankings of tasks by SWAT officers based on frequency, difficulty, and importance and assess if training is addressing traits needed for successful task completion. A survey was designed using Qualtrics (Qualtrics Labs Inc). The survey had a demographics section, performance section, and training section. Officers were contacted by phone or e-mail and asked about interest in participating. Officers who agreed were sent the survey. Our results found a strong correlation between frequency of task and importance (r = 0.69, p = 0.001), and a moderate correlation was found between task difficulty and importance (r = 0.37, p = 0.005). Task rankings were averaged across the 3 domains to assess "overall" importance, and the top 3 tasks were assessed for necessary traits for successful performance. Power and strength were determined to be the most important traits for successful performance. Officers ranked the top 2 focuses of their training program in the training section as stamina/muscular endurance and cardiovascular/respiratory endurance. Training programs for SWAT officers should be developed to improve performance of the tasks with the highest "overall" importance. Therefore, a training program should emphasize strength and power improvements while not neglecting other measures of fitness. [ABSTRACT FROM AUTHOR]

The article presents a study that evaluates whether generic and specific sprinting, and endurance capacity have an effect on the differentiation between the Third-Division and First-Division wheelchair basketball (WB) players. The study was conducted through the use of laboratory tests the assess the performance and physical fitness of the players. The results of the study show that general and specific strength training is an important component of success in basketball competition.

The article focuses on a study conducted for the assessment of certified exercise professional's knowledge pertaining to the guidelines given by American College of Sports Medicine (ACSM) in Guidance for prescribing exercise. It involved an online questionnaire which assessed professional's knowledge related various topics including recommended frequency, duration, and intensity ranges of exercises.