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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.apergo.2010.03.007 Byline: Laura A. Frey Law (a)(b), Jennifer E. Lee (a), Tara R. McMullen (a), Ting Xia (b) Abstract: Ratings of perceived discomfort (0 to 10 scale) have been used to estimate relative maximum holding times (%MHT), particularly for static tasks. A linear 1:10% ratio has been described, where a rating of 5 corresponds to 50%MHT. It is unknown whether this linear ratio is valid for dynamic tasks. Additionally, whether pain or exertion are the primary predictors of discomfort is not clear. Thus, the goal of this study was to investigate both pain and exertion ratings during static (50% maximum; N =42) and dynamic (75% maximum; N =34) elbow flexion tasks until failure. Gender, self-reported physical activity, and peak torque were also assessed. Pain and exertion ratings reasonably matched the 1:10% ratio during the static task but not during the dynamic task. Exertion related more strongly to MHT than pain in both tasks. Neither gender nor activity level appeared to influence perceptual ratings, but peak torque explained approximately 20% of the variance in MHT. Author Affiliation: (a) Graduate Program in Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA 52242, USA (b) Virtual Soldier Research Team, Center for Computer-Aided Design, College of Engineering, The University of Iowa, Iowa City, IA 52242, USA Article History: Received 16 June 2009; Accepted 31 March 2010

The present study is the first to examine whether moderately intense resistance training improves flexibility in an exclusively young, sedentary women population. Twenty-four, young, sedentary women were divided into 3 groups as follows: agonist/antagonist (AA) training group, alternated strength training (AST) group, or a control group (CG). Training occurred every other day for 8 weeks for a total of 24 sessions. Training groups performed 3 sets of 10 to 12 repetitions per set except for abdominal training where 3 sets of 15 to 20 reps were performed. Strength (1 repetition maximum bench press) and flexibility were assessed before and after the training period. Flexibility was assessed on 6 articular movements: shoulder flexion and extension, horizontal shoulder adduction and abduction, and trunk flexion and extension. Both groups increased strength and flexibility significantly from baseline and significantly when compared with the CG (p [less than or equal to] 0.05). The AST group increased strength and flexibility significantly more than the AA group (p [less than or equal to] 0.05) in all but one measurement. This study shows that resistance training can improve flexibility in young sedentary women in 8 weeks. KEY WORDS stretching, resistance training, articular movements, exercise order, physical fitness

The purpose of the present study was to compare the effects of a program of resistance training in water-based exercises (RWE) with those of a program without resistance control in water-based exercises (WEs). Twenty-seven women (aged 60-74 years) were randomly assigned to the RWE group (n = 10), WE group (n = 10), or nontraining control (CON) group (n = 7). The RWE and WE groups trained classes with aerobic exercises and localized muscular resistance exercises for 50 minutes, twice a week for 12 weeks. For the RWE group, the program included 4 mesocycles of 3 weeks-respectively, 4 sets of 15 repetitions, 4 sets of 12 repetitions, 5 sets of 10 repetitions, and 5 sets of 8 repetitions-of shoulder horizontal flexion exercise at maximum speed, with the use of resistive equipment. For the WE group, the training was not periodized, and the resistance in the localized muscular exercises was not controlled. One repetition maximum (1RM) was measured on a pectoral fly machine at baseline and after the training period. The level of significance adopted was p [less than or equal to] 0.05. The results showed that the only significant increase in 1RM (10.89%, p < 0.001) occurred in the RWE group after training. In conclusion, these findings suggest that WEs with emphasis on resistance training in a periodized program can efficiently increase maximum strength in elderly women. Thus, it is suggested that the strategies used in WE programs be modified to offer suitable stimuli for the development of strength. KEY WORDS older adults, aquatic exercise, functional fitness

The purpose of this study was to determine the relationship between squat loads and 2 bilateral and 2 unilateral stepping lower-body exercises in predominantly unilateral movement elite athletes (Karate). Equations to predict loads for lower-body exercises based on the squat load were also determined. Fourteen male elite Karate athletes (age = 22.6 [+ or -] 1.2 years) performed 6 repetition maximum (RM) of the following free-weight bilateral exercises: back half squat, deadlift, leg press and unilateral stepping exercises, lunge; and step-up. Results showed that 6RM squat load was significantly (p < 0.001) correlated with deadlift (r = 0.86), leg press (r = 0.76), lunge (r = 0.86), and step-up (r = 0.92). Linear regression showed that the 6RM squat load was a significant predictor for deadlift, leg press, lunge, and step-up ([R.sup.2] range from 0.57 to 0.85, p < 0.001). The following 6RM prediction equations were determined: (a) Deadlift = squat load (1.12)-16.60 kg, (b) Leg press = squat load (1.66) + 16.10 kg, (c) Lunge = squat load (0.61) + 9.39 kg, and (d) step-up = squat load (0.85)-10.36 kg. Coaches and fitness professionals can use the 6RM squat load as a time effective and accurate method to predict training loads for both bilateral and unilateral lower-body exercises with quadriceps as the prime mover. Load prescriptions for unilateral exercises should take into account the type of athletic population. KEY WORDS load estimates, resistance strength unilateral, bilateral

The purpose of this study was to examine the influence of exercise order on strength and muscle volume (MV) after 12 weeks of nonlinear periodized resistance training. The participants were randomly assigned into 3 groups. One group began performing large muscle group exercises and progressed to small muscle group exercises (LG-SM), whereas another group started with small muscle group exercises and advanced to large muscle group exercises (SM-LG). The exercise order for LG-SM was bench press (BP), machine lat pull-down (LPD), triceps extension (TE), and biceps curl (BC). The order for the SM-LG was BC, TE, LPD, and BP. The third group did not exercise and served as a control group (CG). Training frequency was 2 sessions per week with at least 72 hours of rest between sessions. Muscle volume was assessed at baseline and after 6 weeks and 12 weeks of training by ultrasound techniques. One repetition maximum strength for all exercises was assessed at baseline and after 12 weeks of training. Effect size data demonstrated that differences in strength and MV were exhibited based on exercise order. Both training groups demonstrated greater strength improvements than the CG, but only BP strength increased to a greater magnitude in the LG-SM group as compared with the SM-LG. In all other strength measures (LPD, TE, and BC), the SM-LG group showed significantly greater strength increases. Triceps MV increased in the SM-LG group; however, biceps MV did not differ significantly between the training groups. In conclusion, if an exercise is important for the training goals of a program, then it should be placed at the beginning of the training session, regardless of whether or not it is a large muscle group exercise or a small muscle group exercise. KEY WORDS muscle adaptation, weight lifting, physical fitness, periodization, muscular hypertrophy

The use of elastic bands in resistance training has been reported to be effective in increasing performance-related parameters such as power, rate of force development (RFD), and velocity. The purpose of this study was to assess the following measures during the free-weight back squat exercise with and without elastic bands: peak and mean velocity in the eccentric and concentric phases (PV-E, PV-C, MV-E, MV-C), peak force (PF), peak power in the concentric phase, and RFD immediately before and after the zero-velocity point and in the concentric phase ([RFD.sub.C]). Twenty trained male volunteers (age = 26.0 [+ or -] 4.4 years) performed 3 sets of 3 repetitions of squats (at 55% one repetition maximum [1 RM]) on 2 separate days: 1 day without bands and the other with bands in a randomized order. The added band force equaled 20% of the subjects' 55% 1RM. Two independent force platforms collected ground reaction force data, and a 9-camera motion capture system was used for displacement measurements. The results showed that PV-E and [RFD.sub.C] were significantly (p < 0.05) greater with the use of bands, whereas PV-C and MV-C were greater without bands. There were no differences in any other variables. These results indicate that there may be benefits to performing squats with elastic bands in terms of RFD. Practitioners concerned with improving RFD may want to consider incorporating this easily implemented training variation. KEY WORDS rate of force development, variable resistance training, stretch-shortening cycle

Previous research has shown significantly lower arterial distensibility (AD) after resistance exercise (RE) yet higher AD after aerobic exercise (AE). These changes may be related to exercise-induced differences in vasodilatory capacity. The purpose of this study was to investigate the vasodilatory and AD responses to acute AE and RE. Forearm blood flow (FBF) during reactive hyperemia (RH) was assessed before and 60 minutes after exercise, whereas aortic and femoral pulse wave velocity was measured as an index of arterial stiffness pre, 40, and 60 minutes after an acute bout of AE (30-minute leg ergometry at 650/0 of [[??]o.sub.2]peak) and RE (3 sets, 10 reps; upper and lower body at 65% 1 repetition maximum) in 10 male subjects (24.9 [+ or -] 0.86 years). Area under the curve (AUC) was employed to determine differences in flow. After the intervention, we found that central pulse wave velocity decreased 8% after AE and remained depressed at this level through 60 minutes of observation, whereas RE increased central pulse wave velocity 9.8% from pre to 40 and 60 minutes postexercise. Area under the curve for FBF-RH significantly increased 38% after RE, yet there was no significant change after AE. Forearm vasodilatory capacity increased after acute RE but not after acute AE. This suggests that changes in AD may be disassociated from changes in vasodilatory capacity after acute exercise. Further, in a direct comparison of RE vs. AE, we have shown that RE has greater increases in limb blood flow and augments postexercise hypotension greater at 40 minutes postexercise when compared to AE. KEY WORDS arterial stiffness, blood flow, resistance exercise, vasodilatory capacity, pulse wave velocity

The quest to increase lean body mass is widely pursued by those who lift weights. Research is lacking, however, as to the best approach for maximizing exercise-induced muscle growth. Bodybuilders generally train with moderate loads and fairly short rest intervals that induce high amounts of metabolic stress. Powerlifters, on the other hand, routinely train with high-intensity loads and lengthy rest periods between sets. Although both groups are known to display impressive muscularity, it is not clear which method is superior for hypertrophic gains. It has been shown that many factors mediate the hypertrophic process and that mechanical tension, muscle damage, and metabolic stress all can play a role in exercise-induced muscle growth. Therefore, the purpose of this paper is twofold: (a) to extensively review the literature as to the mechanisms of muscle hypertrophy and their application to exercise training and (b) to draw conclusions from the research as to the optimal protocol for maximizing muscle growth. KEY WORDS muscle development, hypertrophic response, muscle growth, muscle tension, muscle damage, metabolic stress

Agonist-antagonist paired set (APS) training refers to the coupling of agonist and antagonist exercises, performed in an alternating manner with rest intervals between each set. The purpose of this review is to identify the proposed benefits and possible underlying mechanisms of APS training and to suggest how APS training may be exploited. Furthermore, areas deserving of further research attention will be presented. This review will also suggest a common terminology (i.e., APS training) for describing training modalities that alternate agonist and antagonist exercises. Although somewhat equivocal, evidence exists supporting the use of APS as a means of enhancing short-term power measures. Evidence also exists suggesting APS training is an efficacious and efficient means of developing strength and power. Time-efficient methods of developing strength and power would have benefits for athletes and the general population. Athletes able to spend less time developing strength and power would have more time to devote to other aspects of performance or other unrelated tasks. The general population may be more willing to adhere to less time-consuming resistance training programs that offer similar results, as compared to more time-consuming programs. This review concludes that the practical applicability of APS training in terms of acute performance enhancement is limited. However, the use of APS training as an efficacious and time-effective method for developing strength and power may hold some merit. KEY WORDS super set, compound training, strength, complex training, efficiency

The purpose of this study was to determine whether superior concentric performance could be achieved in the bench throw with the use of additional eccentric loads. Fourteen male subjects performed bench throws in a smith machine with an eccentric-concentric load of 40-kg (40-40), and 40-kg concentric with additional eccentric loads of 20 (60-40), 30 (70-40), and 40 kg (80-40). A linear position transducer was used to record displacement-time characteristics, allowing for determination of maximum displacement of the barbell. Differences between the conditions were accepted when p < 0.05. Barbell displacements in the 60- to 40-, 70- to 40-, and 80- to 40-kg eccentric--concentric conditions were all significantly greater than for the 40- to 40-kg eccentric--concentric equated load condition, but no significant difference was observed between each eccentric--concentric load condition. Superior concentric peak barbell displacement can be achieved with additional eccentric loads in the 40-kg bench throw when compared to an equated eccentric-concentric 40- to 40-kg condition, possibly because of greater muscle tension and crossbridging during the eccentric action. Strength and conditioning coaches can use accentuated eccentric load bench throws to elicit greater concentric bench throw performance in athletes. KEY WORDS strength, power, testing, upper body

The purpose of this experiment was to examine upper-body bench throw performance during tests that specifically target different aspects of functional performance. A pool of 26 male, semi-professional rugby league players (age: 23 [+ or -] 3 years, height: 180.8 [+ or -] 5.6 cm, mass: 95.7 [+ or -] 13.0 kg, estimated 1 repetition maximum bench press: 130 [+ or -] 20 kg) volunteered to participate in this study, which consisted of 2 components. First, the reliability of peak force (f) and displacement (d) measured during 4 different types of bench throws was assessed. These tests consisted of full range of motion (ROM) countermovement throws (FC), full ROM static start throws (FS), half ROM countermovement throws (HC), and half ROM static start throws (HS). For all measures, intraclass correlation coefficients were >0.80. The second component of this study examined the relationship between all measures, with a focus on the 2 simplest protocols to implement in an athlete assessment setting--FC and FS. A Pearson's correlation matrix revealed that a combination of [FS.sub.d] and [FS.sub.f] measures was moderately to highly correlated with all outcome measures, whereas neither [FC.sub.d] nor FOr was significantly correlated with [HS.sub.f]--a measure of the athlete's ability to produce force in the midrange of the movement with minimal elastic energy contribution. The results of this study suggest that, in situations where time efficiency is important, assessing full ROM bench throws from a static start may provide a representative measure of both upper-body full and partial ROM performance. KEY WORDS ballistic, weight training, resistance training, biomechanics, power

This study sought to compare the myoelectric activity of the hip adductors (HAs) and rectus femoris (RF) when the hip was in a neutral position or externally rotated by 30[degrees] or 50[degrees] (H0, H30, and H50, respectively) during a parallel squat. Ten healthy subjects performed 10 repetitions of squats in each of the 3 hip positions and the myoelectric activities of the HAs and RF were recorded. The signal was then divided into categories representing concentric (C) and eccentric (E) contractions in the following ranges of motion: 0-30[degrees] (C1 and E1), 30-60[degrees] (C2 and E2), and 60-90[degrees] (C3 and E3) of knee flexion. From those signals, an root mean square (RMS) value for each range of motion in each hip position was obtained. All values were normalized to those obtained during maximum voluntary isometric contraction . We found that HAs showed a significant increase in myoelectric activity during C3 and E3 in the H30 and H50 positions, as compared with H0. Meanwhile, RF activity did not significantly differ between hip positions. Both muscles showed higher activation during 60-90[degrees] (C3 and E3) of knee flexion, as compared with 0-30[degrees] (Cl and E1 ) and 30-60[degrees] (C2 and E2). The results suggest that if the aim is to increase HA activity despite the low percentage of muscle activation, squats should be performed with 30[degrees] of external rotation and at least 90[degrees] of knee flexion. KEY WORDS squat, hip rotation; EMG, biomechanics, resistance training

This study aimed to clarify the relationships between isometric squat (IS) using a back dynamometer and 1 repetition maximum (1RM) squat for maximum force and muscle activities and to examine the effectiveness of a 1 RM estimation method based on IS. The subjects were 15 young men with weight training experience (mean age 20.7 [+ or -] 0.8 years, mean height 171.3 [+ or -] 4.4 cm, mean weight 64.4 [+ or -] 8.4 kg). They performed the IS with various stance widths and squat depths. The measured data of exerted maximum force and the action potential of the agonist muscles were compared with the 1RM squat data. The exerted maximum force during IS was significantly larger in wide stance (140% shoulder width) than in narrow stance (5-cm width). The maximum force was significantly larger with decreased knee flexion. As for muscle activity, the % root mean square value of muscle electric potential of the rectus femoris and the vastus lateralis tended to be higher in wide stance. As for exerted maximum force, wide stance and parallel depth in IS showed a significant and high correlation (r = 0.73) with 1RM squat. Simple linear regression analysis revealed a significant estimated regression equation [Y = 0.992X + 30.3 (Y:I RM, X:IS)]. However, the standard error of an estimate value obtained by the regression equation was very large (11.19 kg). In conclusion, IS with wide stance and parallel depth may be useful for the estimation of 1RM squat. However, estimating a 1RM by IS using a back dynamometer may be difficult. KEY WORDS 1RM squat, isometric, back dynamometer, estimation method

The objective of this study was to investigate the acute effects on volume load (VL) (load x repetitions) of performing paired set (PS) vs. traditional set (TS) training over 3 consecutive sets. After a familiarization session 16 trained men performed 2 testing protocols using 4 repetition maximum loads: TS (3 sets of bench pull followed by 3 sets of bench press performed in approximately 10 minutes) or PS (3 sets of bench pull and 3 sets of bench press performed in an alternating manner in approximately 10 minutes). Bench pull and bench press VL decreased significantly from set 1 to set 2 and from set 2 to set 3 under both the PS and TS conditions (p < 0.05). Bench pull and bench press VL per set were significantly less under TS as compared to PS over all sets, with the exception of the first set (bench pull set 1) (p < 0.05). Session totals for bench pull and bench press VL were significantly less under TS as compared to PS (p < 0.05). Paired set was determined to be more efficient (VL/time) as compared to TS. The data suggest that a 2-minute rest interval between sets (TS), or a 4-minute rest interval between similar sets (PS), may not be adequate to maintain VL. The data further suggest that PS training may be more effective than TS training in terms of VL maintenance and more efficient. Paired set training would appear to be an efficient method of exercise. Practitioners wishing to maximize work completed per unit of time may be well advised to consider PS training. KEY WORDS paired set, bench press, bench pull, complex training

McGuigan, MR, Newton, MJ, Winchester, JB, and Nelson, AG. Relationship between isometric and dynamic strength in recreationally trained men. Strength Cond Res 24(9): 2570-2573, 2010--The purpose of this investigation was to examine the relationships between measures of maximal isometric force (peak force [PF]), rate of force development (RFD), vertical jump performance (VJ) and 1-repetition maximum (1RM) strength in recreationally trained men. The subjects in this study were 26 men ([mean [+ or -] SD]: age 22 [+ or -] 1 years; height 175 [+ or -] 7 cm; mass 90 [+ or -] 10 kg). They were tested for PF using the isometric midthigh pull exercise. The 1RM for the squat and bench press exercise were determined as a measure of dynamic strength. Explosive strength was measured as RFD from the isometric force-time curve. Correlations between the variables were calculated using Pearson product moment correlation coefficient. There was a nearly perfect correlation between measures of PF and 1RM squat (r = 0.97, p < 0.05) and 1RM bench press (r = 0.99, p < 0.05). The correlations were very strong between VJ and PF (r = 0.72, p < 0.05) and 1RM bench press (r = 0.70, p < 0.05). There were also strong correlations between VJ and 1RM squat (r = 0.69, p < 0.05). There were no significant correlations with RFD. The results showed that isometric maximum strength determined during the isometric midthigh pull test correlated well with 1RM and VJ testing. However, RFD measured during the same test did not appear to correlate as well with other measures. The isometric midthigh pull provides an efficient method for assessing strength in recreationally trained individuals. Practioners wishing to obtain performance data related to maximum strength may wish to consider isometric testing as a less time intensive method of testing. KEY WORDS isometric strength, power, vertical jump 1 repetition maximum, resistance training

Cakir-Atabek, H, Demir, S, Pinarbasili, RD, and Gunduz, N. Effects of different resistance training intensity on indices of oxidative stress. J Strength Cond Res 24(9): 2491-2497, 2010--The purposes of this study were (a) to determine whether acute resistance exercise training (RET) induces oxidative stress, (b) to determine whether chronic RET decreases oxidative stress level at rest condition in previously untrained men, and (c) also to investigate how the RET intensity influences the training-induced oxidative stress response. Sixteen young men who did not have RET experience in the past were randomly divided in 2 groups. Hypertrophy-intensity group (n = 9) performed 3 sets of 12 repetitions at an intensity corresponding to 70% of 1 repetition maximum (1RM), whereas strength-intensity group (n = 7) performed 3 sets of 6 repetitions at an intensity corresponding to 85% of 1RM. Resistance exercise training involved 6 exercises, and it was performed 3 times a week on nonconsecutive days for 6 weeks. Blood samples were obtained just before (pre-RET) and immediately after RET (post-RET) on the first day of the first week, on the last day of the fourth and sixth weeks. The results indicated that malondialdehyde (MDA) significantly decreased (p < 0.05) in both groups immediately after RET; however, there was no significant acute alteration in glutathione (GSH) level in both groups (p > 0.05). After 6 weeks of training, pre-RET values of MDA significantly decreased and pre-RET values of GSH significantly increased in both hypertrophy- and strength-intensity groups (p < 0.05). These alterations occurred independently of training intensity. This study indicated that hypertrophy- and strength-intensity whole-body RET performed regularly for 6 weeks, decreased MDA concentration and increased GSH level in healthy young men. Results suggest that chronic RET has protective effects against oxidative stress similar to aerobic exercises and that these effects seem to be independent of the training intensity. KEY WORDS hypertrophy strength, exercise; reduced glutathione (GSH), malondialdehyde (MDA)

Garcia-Lopez, D, Herrero, AJ, Gonzalez-Calvo, G, Rhea, MR, and Marin, PJ. Influence of 'in series' elastic resistance on muscular performance during a biceps-curl set on the cable machine. J Strength Cond Res 24(9): 2449-2455, 2010--This study aimed to investigate the role of elastic resistance (ER) applied 'in series' to a pulley-cable (PC) machine on the number of repetitions performed, kinematics parameters, and perceived exertion during a biceps-curl set to failure with a submaximal load (70% of the 1 repetition maximum). Twenty-one undergraduate students (17 men and 4 women) performed, on 2 different days, 1 biceps-curl set on the PC machine. Subjects were randomly assigned to complete 2 experimental conditions in a cross-over fashion: conventional PC mode or ER + PC mode. Results indicate ER applied 'in series' to a PC machine significantly reduces (p < 0.05) the maximal number of repetitions and results in a smooth and consistent decline in mean acceleration throughout the set, in comparison to the conventional PC mode. Although no significant differences were found concerning intrarepetition kinematics, the ER trended to reduce (18.6%) the peak acceleration of the load. With a more uniformly distributed external resistance, a greater average muscle tension could have been achieved throughout the range of movement, leading to greater fatigue that could explain the lower number of maximal repetitions achieved. The application of force in a smooth, consistent fashion during each repetition of an exercise, while avoiding active deceleration, is expected to enhance the benefits of the resistance exercise, especially for those seeking greater increases in muscular hypertrophy. KEY WORDS elastic tension, accommodate resistance, weight training, kinematics, muscle tension

Hermassi, S, Chelly, MS, Fathloun, M, and Shephard, RJ. The effect of heavy-vs. moderate-load training on the development of strength, power, and throwing ball velocity in male handball players. J Strength Cond Res 24(9): 2408-2418, 2010--The aim was to compare the effect of 2 differing 10-week resistance training programs on the peak power (PP) output, muscle volume, strength, and throwing velocity of the upper limbs in handball players during the competitive season. The subjects were 26 men (age 20.0 [+ or -] 0.6 years, body mass 85.0 [+ or -] 13.2 kg, height 1.86 [+ or -] 0.06 m, and body fat 13.7 [+ or -] 2.4%). They were randomly assigned to 1 of 3 groups: control (C; n = 8), heavy resistance (n = 9), or moderate resistance (MR; n = 9) training, performed twice a week. A force-velocity test on an appropriately modified Monark cycle ergometer determined PP. Muscle volumes were estimated using a standard anthropometric kit. One-repetition maximum (1RM) bench press ([1RM.sub.BP]) and 1RM pull-over ([1RM.sub.PO]) scores assessed arm strength. Handball throwing velocity was measured with ([T.sub.R]) and without run-up ([T.sub.w]). Both training programs enhanced absolute PP relative to controls (p < 0.05), although differences disappeared if PP was expressed per unit of muscle volume. Heavy resistance-enhanced [1RM.sub.BP] and [1RM.sub.PO] compared to both MR (p < 0.01 and p < 0.05, respectively) and C (p < 0.001 for both tests). Heavy resistance also increased [T.sub.R] and [T.sub.W] compared to C (p < 0.01 and p < 0.05, respectively). Moderate resistance increased only [T.sub.R] compared to C (p < 0.01). Thus, during the competitive season, the PP, [1RM.sub.BP], [1RM.sub.PO], and [T.sub.w] of male handball players were increased more by 10 weeks of bench press and pull-over training with suitably adapted heavy loads than with moderate loads. It would seem advantageous to add such resistance exercise before customary technical and tactical handball training sessions. KEY WORDS arm throwing, maximal strength, upper extremity, throwing performance

DeFreitas, JM, Beck, TW, Stock, MS, Dillon, MA, Sherk, VD, Stout, JR, and Cramer, JT. A comparison of techniques for estimating training-induced changes in muscle cross-sectional area. J Strength Cond Res 24(9): 2383-2389, 2010--The ability to accurately estimate changes in muscle cross-sectional area (CSA) could be a useful tool for strength and conditioning practitioners to assess the effectiveness of a resistance training program. The purpose of this study was twofold: (a) to compare the reliability of 2 separate anthropometric-based field estimations of thigh muscle CSA with that of a more accurate, sophisticated imaging technique (peripheral quantitative computed tomography [pQCT] scanner) and (b) to determine if the field methods would be sensitive enough to detect changes in CSA during a resistance training program. Twenty-five healthy, untrained men completed 8 weeks of resistance training. Cross-sectional area testing occurred twice before the start of training, for reliability and again every 2 weeks during the study. Testing consisted of a pQCT scan of the right thigh followed by circumference and skinfold measurements. Two separate equations (Moritani and deVries [M + D] and Housh multiple regression [HMR]) were used to estimate CSA from the anthropometric data. The M + D and HMR methods demonstrated intraclass correlations of 0.983 and 0.961, respectively, but both significantly underestimated thigh muscle CSA when compared to the pQCT. This error was consistent, however, and consequently, the field methods were able to demonstrate increases in muscle CSA with a pattern similar to those from the pQCT. Thus, these equations can be useful tools to evaluate an athlete's progress toward the goal of increasing muscle CSA. It is the authors' hope that the present study will increase awareness among practitioners of these useful field methods for estimating training-induced changes in muscle CSA. KEY WORDS anthropometry; pQCT, hypertrophy

Berning, JM, Adams, KJ, DeBeliso, M, Sevene-Adams, PG, Harris, C, and Stamford, BA. Effect of functional isometric squats on vertical jump in trained and untrained men. J Strength Cond Res 24(9): 2285-2289, 2010-Functional isometrics (FIs) combine dynamic and isometric muscle actions and may hyperstimulate the nervous system leading to an enhanced postactivation potentiation (PAP) and improved subsequent performance. The purpose of this study was to investigate the impact of an FI squat on the countermovement vertical jump (CMVJ) in resistance trained and untrained men. Thirteen trained men (age: 22.8 [+ or -] 3.2 years, mass: 90.0 [+ or -] 16.3 kg, and height: 178.9 [+ or -] 7.1 cm) and 8 untrained men (age: 28.5 [+ or -] 5.9 years, mass: 101.5 [+ or -] 23.0 kg, and height: 177.0 [+ or -] 4.8 cm) participated. On separate days, subjects performed CMVJs after 2 different warm-up conditions. The warm-up conditions consisted of either 5 minutes of low-intensity cycling or 5 minutes of low-intensity cycling plus a 3-second FI squat with 150% of their 1 repetition maximum (1RM). A 2 x 3 repeated-measures analysis of variance with Bonferroni post hoc revealed that when comparing the 2 warm-up conditions in the trained subjects, a significant increase (p < 0.05) in CMVJ occurred at 4 minutes (2.4 cm, +5.1%) post-FI squat. This increase was maintained when subjects were retested at 5 minutes post (2.6 cm, + 5.5%). No significant difference in CMVJ was detected in the untrained group (p = 0.49). Results support the addition of an FI squat performed at 150% of 1RM to a low-intensity cycling warm-up to enhance PAP in resistance trained but not in untrained men as measured by CMVJ. Practically, adding functional isometrics to a warm-up scheme may significantly enhance acute, short-term power output in resistance trained men.

Kistler, BM, Walsh, MS, Horn, TS, and Cox, RH. The acute effects of static stretching on the sprint performance of collegiate men in the 60- and 100-m dash after a dynamic warm-up. J Strength Cond Res 24(9): 2280-2284, 2010-Previous research has shown that static stretching has an inhibitory effect on sprinting performances up to 50 m. The purpose of this study was to see what would happen to these effects at longer distances such as those seen in competition. This study used a within-subjects design to investigate the effects of passive static stretching vs. no stretching on the 60- and 100-m sprint performance of college track athletes after a dynamic warm-up. Eighteen male subjects completed both the static stretching and the no stretching conditions in counterbalanced order across 2 days of testing. On each day, all subjects first completed a generalized dynamic warm-up routine that included a self-paced 800-m run, followed by a series of dynamic movements, sprint, and hurdle drills. At the end of this generalized warm-up, athletes were assigned to either a static stretching or a no-stretching condition. They then immediately performed 2 100-m trials with timing gates set up at 20, 40, 60, and 100 m. Results revealed a significant slowing in performance with static stretching (p < 0.039) in the second 20 (20-40) m of the sprint trials. After the first 40 m, static stretching exhibited no additional inhibition of performance in a 100-m sprint. However, although there was no additional time loss, athletes never gained back the time that was originally lost in the first portion of the trials. Therefore, in strict terms of performance, it seems harmful to include static stretching in the warm-up protocol of collegiate male sprinters in distances up to 100 m. KEY WORDS stiffness, neural activation, resistance

Muscle protein breakdown (MPB) is increased following resistance exercise, but ingestion of carbohydrate during postexercise recovery can decrease MPB with no effect on muscle protein synthesis (MPS). We sought to determine whether a combination of essential amino acids (EAA) with low carbohydrate or high carbohydrate could effectively reduce MPB following resistance exercise and improve muscle protein net balance (NB). We hypothesized that higher levels of carbohydrate and resulting increases in circulating insulin would inhibit MPB and associated signaling, resulting in augmented NB. Thirteen male subjects were assigned to one of two groups receiving equivalent amounts of EAA (~20 g) but differing carbohydrate levels (low = 30, high = 90 g). Groups ingested nutrients 1 h after an acute bout of leg resistance exercise. Leg phenylalanine kinetics (e.g., MPB, MPS, NB), signaling proteins, and mRNA expression were assessed on successive muscle biopsies using stable isotopic techniques, immunoblotting, and real-time quantitative PCR, respectively. MPB tended to decrease (P < 0.1) and MPS increased (P < 0.05) similarly in both groups following nutrient ingestion. No group differences were observed, but muscle ring finger 1 (MuRF1) protein content and MuRF 1 mRNA expression increased following resistance exercise and remained elevated following nutrient ingestion, while autophagy marker (light-chain 3B-II) decreased after nutrient ingestion (P < 0.05). Forkhead box-O3a phosphorylation, total muscle atrophy F-box (MAFbx) protein, and MAFbx and caspase-3 mRNA expression were unchanged. We conclude that the enhanced muscle protein anabolic response detected when EAA+carbohydrate are ingested post-resistance exercise is primarily due to an increase in MPS with minor changes in MPB, regardless of carbohydrate dose or circulating insulin level. muscle proteolysis; muscle protein metabolism; atrogin-1; MuRF1; LC3B doi: 10.1152/ajpregu.00077.2010.

This study tested the hypothesis that resveratrol supplementation would lower oxidative stress in exercised muscles of aged mice. Young (3 months) and aged (27 months) C57BL/6 mice received a control or a 0.05% trans-resveratrol-supplemented diet for 10 days. After 7 days of dietary intervention, 20 maximal electrically evoked isometric contractions were obtained from the plantar flexors of one limb in anesthetized mice. Exercise was conducted for three consecutive days. Resveratrol supplementation blunted the exercise-induced increase in xanthine oxidase activity in muscles from young (25%) and aged (53%) mice. Resveratrol lowered H202 levels in control (13%) and exercised (38%) muscles from aged animals, reduced Nox4 protein in both control and exercised muscles of young (30%) and aged mice (40%), and increased the ratio of reduced glutathione to oxidized glutathione in exercised muscles from young (38%) and aged (135%) mice. Resveratrol prevented the increase in lipid oxidation, increased catalase activity, and increased MnSOD activity in exercised muscles from aged mice. These data show that dietary resveratrol suppresses muscle indicators of oxidative stress in response to isometric contractions in aged mice. Key Words: Exercise--Oxidative stress--Sarcopenia--Xanthine oxidase activity--NAD(P)H oxidase activity. doi: 10.1093/gerona/glq080

The popularity of resistance training (RT) is evident by the more than 45 million Americans who engage in strength training regularly. Although the health and fitness benefits ascribed to RT are generally agreed upon, participation is not without risk. Acute and chronic injuries attributed to RT have been cited in the epidemiological literature among both competitive and recreational participants. The shoulder complex in particular has been alluded to as one of the most prevalent regions of injury. The purpose of this manuscript is to present an overview of documented shoulder injuries among the RT population and where possible discern mechanisms of injury and risk factors. A literature search was conducted in the PUBMED, CINAHL, SPORTDiscus, and OVID databases to identify relevant articles for inclusion using combinations of key words: resistance training, shoulder, bodybuilding, weightlifting, shoulder injury, and shoulder disorder. The results of the review indicated that up to 36% of documented RT-related injuries and disorders occur at the shoulder complex. Trends that increased the likelihood of injury were identified and inclusive of intrinsic risk factors such as joint and muscle imbalances and extrinsic risk factors, namely, that of improper attention to exercise technique. A majority of the available research was retrospective in nature, consisting of surveys and descriptive epidemiological reports. A paucity of research was available to identify predictive variables leading to injury, suggesting the need for future prospective-based investigations. KEY WORDS shoulder pain, resistance training injury, bodybuilding, weightlifting

The purpose of the current study was to compare serum creatine kinase (CK) and lactate dehydrogenase (LDH) concentrations at multiple time points after resistance exercise sessions that incorporated different rest intervals between sets and exercises. Twenty untrained men (18.65 [+ or -] 0.49 years, 68.30 [+ or -] 7.98 kg, and 174.4 [+ or -] 4.80 cm) performed 2 resistance exercise sessions (i.e., 3 sets with 80% 1 repetition maximum for 5 upper-body exercises) with either 1-minute (SEQ1) or 3-minute (SEQ3) rest between sets and exercises. For each session, CK and LDH concentrations were measured before exercise (PRE) and 24, 48, and 72 hours after exercise (24P, 48P, and 72P). Subjects lifted a 24% greater (p < 0.05) volume load during SEQ3 than during SEQ1. Within SEQ1, significant differences in OK concentrations were demonstrated between most time points, except between 24P and 72P. Similarly, within SEQ3, significant differences in CK concentrations were demonstrated between most time points, except between 24P and 72P and between 48P and 72P. The CK concentrations were highest at 48P for both sessions. When the CK concentrations were compared between SEQ1 and SEQ3, no significant differences were demonstrated at any time point. Within SEQ1, a significant difference in LDH concentration was demonstrated between 48P and 72P. Within SEQ3, significant differences in LDH concentrations were demonstrated between PRE and 24P and between PRE and 48P. The LDH concentrations were highest at 72P for SEQ1 and at 24P for SEQ3. When the LDH concentrations were compared between SEQ1 and SEQ3, no significant differences were demonstrated at any time point. These results suggest that muscle damage was similar between rest intervals; however, the volume load completed to induce the muscle damage was significantly greater when 3-minute rest intervals were employed. Therefore, when considered relative to the volume load completed, 1-minute rest intervals during resistance exercise may invoke greater muscle damage. KEY WORDS recovery time, exercise volume, muscle damage, muscular stress, biochemical markers

Popular fitness literature suggests that varying the elbow range of motion (ROM) during the Military press can lead up to specific muscle isolation especially for deltoid and trapezius muscles. The purpose of the study was to examine the effect of ROM at different loads on the electromyographic (EMG) activity of 8 preselected muscles. Six experienced lifters performed 3 sets of 10 repetitions, each one with a different ROM: the first one with a final elbow angle of 90[degrees] (R1); the second with 135[degrees] (R2), and the last one with a final elbow angle of 180[degrees] (R3). Three resistances were chosen (no load, 30% of one repetition maximum [1-RM], and 70% of 1-RM), and sets were separated by 5 minutes rest. Electromyographic surface electrodes were placed on the clavicular head of pectoralis major, anterior deltoid, medial deltoid (MD), posterior deltoid (PD), upper trapezius, middle trapezius (MT), long head of triceps, and teres minor (TM). Analysis of variance showed a significant increase of rmsEMG activation with the widest ROM for each muscle and for each load condition except in MT and TM and PD with no load. The results showed that the use of the widest ROM increased the EMG activity of all the muscles selected with respect to the closest one, whereas this effect is not totally confirmed with the employment of R2. In addition, the use of intermediate ROMs was able to isolate the activity of the MD with respect to the trapezius only in the condition of the heaviest load. This suggests to coaches that in strength development programs the employment of an incomplete ROM can reduce the involvement of the trapezius without decreasing medium deltoid activation only with heavy loads. KEY WORDS muscle activity, muscle isolation, resistance training

The purpose of this study was to analyze the influence of exercise type, set configuration, and relative intensity load on relationship between 1 repetition maximum (1RM) and maximum number of repetitions (MNR). Thirteen male subjects, experienced in resistance training, were tested in bench press and biceps curl for 1RM, MNR at 90% of 1RM with cluster set configuration (rest of 30s between repetitions) and MNR at 70% of 1RM with traditional set configuration (no rest between repetitions). A lineal encoder was used for measuring displacement of load. Analysis of variance analysis revealed a significant effect of load (p < 0.01) and a tendency in exercise factor (p = 0.096), whereas the interaction effect was not significant. MNR at 70% of 1RM was lower for biceps curl (16.31 [+ or -] 2.59 vs. 8.77 [+ or -] 3 in bench press and biceps curl, respectively; p < 0.05) and at 90% of 1RM (21.85 [+ or -] 11.06 vs. 18.54 [+ or -] 12.84 in bench press and biceps curl, respectively; p > 0.05). Correlation between 1 RM and MNR was significant for medium-intensity in biceps curl (r = -0.574; p < 0.05) and between MNR and 1RM/body mass (r = -0.574; p < 0.05). Neither 1RM nor 1RM/body mass correlated with velocity along set, so velocity seems to be similar at a same relative intensity for subjects with differences in maximum strength levels. From our results, we suggest the employment of MNR rather than % of 1RM for training monitoring. Furthermore, we suggest the introduction of cluster set configuration for upper-body assessment of MNR and for upper-body muscular endurance training at high-intensity loads, as it seems an efficient approach in looking for sessions with greater training volumes. This could be an interesting approach for such sports as wrestling or weightlifting. KEY WORDS set configuration, resistance training, bench press, biceps curl

The purpose of this study was to compare repetition performance when resting 1 minute vs. 3 minutes between sets and exercises for an upper-body workout performed in 2 different sequences. Sixteen recreationally trained men completed 4 experimental resistance exercise sessions. All sessions consisted of 3 sets with an 8-repetition maximum load for 6 upper-body exercises. Two different exercise sequences (i.e., A or B) were performed with either 1- or 3-minute rest between sets and exercises, respectively. For sequence A1 (SEQA1) and sequence A3 (SEQA3), resistance exercises were performed in the following order: lat pull-down with a wide grip (LPD-WG), lat pull-down with a close grip (LPD-CG), machine seated row (SR-M), barbell row lying on a bench (BR-B), dumbbell seated arm curl (SAC-DB), and machine seated arm curl (SAC-M). Conversely, for sequence B1 (SEQB1) and sequence B3 (SEQB3), the exercises were performed in the opposite order. The results demonstrated that the effect of exercise order was stronger than the effect of rest interval length for LPD-WG (SEQA3 > SEQA1 > SEQB3 > SEQB1) and SAC-M (SEQB3 > SEQB1 > SEQA3 > SEQA1), whereas the effect of rest interval length was stronger than the effect of exercise order for LPD-CG, SR-M, SAC-DB (SEQA3 = SEQB3 > SEQA1 = SEQB1), and BR-B (SEQB3 > SEQA3 = SEQB1 > SEQA1). These results suggest that upper-body exercises involving similar muscle groups and neural recruitment patterns are negatively affected in terms of repetition performance when performed at the end vs. the beginning of a session, and the reduction in repetition performance is greater when using 1-minute vs. 3-minute rest interval between sets. KEY WORDS strength, fatigue, recovery, volume, repetition, performance

This study aimed to investigate relationships between peak power (PP) as measured by upper limb ([PP.sub.UL]) and lower limb ([PP.sub.LL]) force--velocity tests, maximal upper limb force assessed by 1 repetition maximum bench press ([1RM.sub.BP]), and pullover ([1RM.sub.PO]) exercises, estimates of local muscle volume and 3-step running handball throwing velocity ([T.sub.3-Steps]), Fourteen male handball players volunteered for the investigation (age: 19.6 [+ or -] 0.6 years; body mass: 86.7 [+ or -] 12.9 kg; and height 1.87 [+ or -] 0.07 m). Lower and upper limb force--velocity tests were performed on appropriately modified forms of a Monark cycle ergometer, with measurement of [PP.sub.UL] and [PP.sub.LL], and the corresponding respective maximal forces ([F.sub.OUL] and [F.sub.OLL]) and velocities ([V.sub.OUL] and [V.sub.OLL]). [T.sub.3-steps] was assessed using a radar Stalker ATS system[TM]. Muscle volumes of the upper and lower limbs were estimated with a standard anthropometric kit. [T.sub.3-steps] was closely related to absolute [PP.sub.UL] and to [F.sub.OUL] (r = 0.69, p < 0.01 for both relationships). [T.sub.3-Steps] was also moderately related to [1RM.sub.BP] and [1RM.sub.PO] (r = 0.56, p < 0.05; r = 0.55, p < 0.05 respectively), and to [PP.sub.LL] and [F.sub.OLL] (r = 0.56, p < 0.05; r = 0.62, p < 0.05, respectively). When [PP.sub.LL] was expressed per unit of limb muscle volume, the relationship with [T.sub.3-steps] disappeared. This suggests the importance of muscle volume to performance in throwing events. Force--velocity data may prove useful in regulating conditioning and rehabilitation programs for handball players. Our results also highlight the contribution of both the lower and the upper limbs to handball throwing velocity, suggesting the need for coaches to include upper and lower limb strength and power programs when improving the throwing velocity of handball players. KEY WORDS force--velocity test, maximal repetition tests, muscle volume, anthropometry, resistance conditioning

The purpose of this investigation was to determine the effect of different lifting cadences on the ground reaction force (GRF) during the squat exercise. Squats performed with greater acceleration will produce greater inertial forces; however, it is not well understood how different squat cadences affect GRF. The hypotheses were that faster squat cadences would result in greater peak GRF and that the contributions of the body and barbell, both of equivalent mass, to total system inertial force would not be different. Six experienced male subjects (31 [+ or -] 4 years, 180 [+ or -] 9 cm, 88.8 [+ or -] 13.3 kg) performed 3 sets of 3 squats using 3 different cadences (fast cadence [FC] = 1-second descent/1-second ascent; medium cadence [MC] = 3-second descent/1-second ascent; and slow cadence [SC] = 4-second descent/2-second ascent) while lifting a barbell mass equal to their body mass. Ground reaction force and velocity sensor data were used to calculate inertial force contributions of both the body and barbell to total inertial force. Peak GRF were significantly higher in FC squats compared to MC (p = 0.0002) and SC (p = 0.0002). Ranges of GRF were also significantly higher in FC compared to MC (p < 0.05) and higher in MC compared to SC (p < 0.05). The inertial forces associated with the body were larger than those associated with the barbell, regardless of cadence. Faster squat cadences result in significantly greater peak GRF as a result of the inertia of the system. This study demonstrates that GRF was more dependent on descent cadence than on ascent cadence and that researchers should not use a single point on the body to approximate the location of the center of mass during squat exercise analysis. Key Words velocity, inertial forces, weight training, resistive exercise

This study analyzed the postexercise blood pressure (BP) after resistance exercise (RE) on middle-aged type-2 diabetic (T2DM, n = 10, 46.6 [+ or -] 13.1 years) and nondiabetic subjects (NDM, n = 10, 52.0 [+ or 0] 13.2 years). Participants performed (a) 1 repetition maximum (1RM) strength test; (b) 3 laps in an RE circuit of 6 exercises (16 repetitions at 43% 1RM); (c) 3 laps in an RE circuit (30 repetitions at 23% 1RM); and (d) a control session. The blood lactate concentration ([lac]) (YSI 2700S) and BP (Microfife BP3AC1-1) were measured pre-exercise, after exercise, and at each 15 minutes during the 120 minutes of recovery. Analysis of variance with Bonferroni as a post hoc evidenced that the 43% 1RM session elicited the highest [lac] response for both NDM (7.8 [+ or 0] 1.8 vs. 6.4 [+ or -] 1.8 mmol x [L.sup.-1]; p < 0.05) and T2DM (7.0 [+ or -] 1.4 vs. 5.6 [+ or -] 1.6 mmol x [L.sup.-1]; p < 0.05). Also, the 43% 1RM session promoted a significant postexercise hypotension (PEH) of systolic blood pressure (SBP) and mean arterial pressure (MAP), whereas the 23% 1RM did not. The highest BP reductions for T2DM and NDM after 43% 1RM were, respectively, 9.5 [+ or -] 11.1and 11.0 [+ or -] 7.1 mmHg for SBP and 6.4 [+ or -] 7.8 and 7.7 [+ or -] 7.9 mmHg for the MAP (p [less than or equal to] 0.05). The PEH of SBP lasted longer (120 minutes) for NDM than for T2DM (90 minutes). The PEH may be associated with [lac] elevation, and the lower hypotensive effect presented by T2DM may be related to endothelial dysfunction usually observed in diabetic individuals. In conclusion, the RE of higher intensity, performed in ~25-minute duration, was more efficient at promoting PEH which, in turn, suggests its use on BP control for middle-aged T2DM and NDM subjects with characteristics similar to those of our participants. KEY WORDS resistance exercise, diabetes, blood pressure control, postexercise hypotension, blood lactate

The objective of this study was to (a) evaluate the impact of the leg press, at variable percentages of 1 repetition maximum (1RM), on heart rate variability (HRV) and blood lactate and (b) determine the relationship between HRV with blood lactate in a healthy elderly cohort. Ten healthy men (64 [+ or -] 4 years) participated in a progressive leg-press protocol to maximal exertion. Initially, 1RM for the leg press was determined for all subjects. The protocol then began at 10% of 1 RM, with subsequent increases of 10% until 30% of 1RM, followed by incremental adjustments of 5% until exhaustion. The measurement of instantaneous R-R interval variability from Poincare plots (SD1 and SD2) and time domain indexes (RMSSD and RMSM), blood pressure, and blood lactate were obtained at rest and all leg-press loads. Significant alterations of HRV and blood lactate were observed from 30% of 1RM leg press (p < 0.05). Additionally, significant correlations were found between the lactate threshold (LT) and the RMSSD threshold (r = 0.78; p < 0.01), and between the LT and SD1 threshold (r = 0.81, p < 0.01). We conclude that metabolic and cardiovascular alterations are apparent during relatively low resistance exercise (RE) loads in apparently healthy subjects. In addition, HRV indexes were associated with blood-lactate levels during RE. The practical applications is the possibility of using HRV as a noninvasive measure obtained at a relatively low cost may be used to identify neural and metabolic alterations during RE in older subjects. Key Words autonomic nervous system, anaerobic threshold, strength exercise, aging

The hallmark characteristic of chronic heart failure (CHF) is exercise intolerance. This study evaluated a combined exercise program that would be consistent with current cardiac rehabilitation guidelines. The program consisted of progressive resistance training (intensity progressing from 50 to 80% maximum) and aerobic conditioning (70% of heart rate reserve). Outcomes included muscular strength measured as 8-repetition maximum and submaximal aerobic fitness indicators (measured at 50% of predicted maximal oxygen consumption) including heart rate, blood pressure, and rate pressure product. Subjects were taken retrospectively from a database of CHF patients who underwent cardiac rehabilitation between 1998 and 2004 with the Cardiac Rehabilitation Center of River Cities Cardiology in Jeffersonville, IN. The same data set was used to evaluate 2 research questions: to compare training outcomes between gender (men and women) and to compare outcomes between young ([less than or equal to] 65 years) and old (>65 years) subjects. Forty-two subjects (15 women and 27 men; 19 were [less than or equal to] 65 and 23 were >65 years of age) met inclusion and exclusion criteria and underwent 36 sessions of cardiac rehabilitation over a 14-week time period. Repeated-measures analysis of variance was used to test whether strength and submaximal responses differed across gender or age. Analysis indicated that regardless of gender or age, subjects significantly increased their strength on each of 6 strength tests. Heart rate, systolic blood pressure, and rate pressure product were lower after training indicating increased aerobic efficiency. Progressive resistance training and aerobic conditioning prescribed in a manner consistent with cardiac rehabilitation guidelines resulted in similar improvements regardless of gender or age for individuals with CHF suggesting that no training program adjustments are necessary to accommodate age or gender. KEY WORDS heart, disease, strength, endurance, muscle fitness

Nonselective blockade of the cyclooxygenase (COX) enzymes in skeletal muscle eliminates the normal increase in muscle protein synthesis following resistance exercise. The current study tested the hypothesis that this COX-mediated increase in postexercise muscle protein synthesis is regulated specifically by the COX-2 isoform. Sixteen males (23 [+ or -] 1 yr) were randomly assigned to one of two groups that received three doses of either a selective COX-2 inhibitor (celecoxib; 200 rag/dose, 600 mg total) or a placebo in double-blind fashion during the 24 h following a single bout of knee extensor resistance exercise. At rest and 24 h postexercise, skeletal muscle protein fractional synthesis rate (FSR) was measured using a primed constant infusion of [[sup.2][H.sub.5]]phenylalanine coupled with muscle biopsies of the vastus lateralis, and measurements were made of mRNA and protein expression of COX-1 and COX-2. Mixed muscle protein FSR in response to exercise (P < 0.05) was not suppressed by the COX-2 inhibitor (0.056 - 0.004 to 0.108 -+ 0.014%/h) compared with placebo (0.074 _+ 0.004 to 0.091 -+ 0.005%/h), nor was there any difference (P > 0.05) between the placebo and COX-2 inhibitor postexercise when controlling for resting FSR. The COX-2 inhibitor did not influence COX-1 mRNA, COX-1 protein, or COX-2 protein levels, whereas it did increase (P < 0.05) COX-2 mRNA (3.0 [+ or -] 0.9-fold) compared with placebo (1.3 _+ 0.3-fold). It appears that the elimination of the postexercise muscle protein synthesis response by nonselective COX inhibitors is not solely due to COX-2 isoform blockade. Furthermore, the current data suggest that the COX-1 enzyme is likely the main isoform responsible for the COX-mediated increase in muscle protein synthesis following resistance exercise in humans. celecoxib; [sup.2][H.sub.5] phenylalanine; resistance exercise doi: 10.1152/ajpendo.00423.2009

Although adaptations to water-based resistance exercise and conventional water-based exercise have been investigated, little is known regarding acute anabolic and catabolic hormonal responses to these 2 types of exercise. The purpose of this study was to investigate the acute responses of salivary testosterone and cortisol to 2 water-based exercise protocols in which the different intensities were determined using Borg's perceived exertion scale. Ten young (24 [+ or -] 2.7 yr) and 7 elderly men (65 [+ or -] 5.5 yr) who were familiar with exercise in water were subjects of the study. Salivary samples were collected at rest and 5 minutes after the 2 water-based exercise protocols. One session involved intermittent water resistance training at a Borg-scale intensity of 19 (W19), whereas the other involved continuous water aerobic training at an intensity of 13 (W13). The samples were used to determine salivary levels of free testosterone and cortisol. There was a significant increase on salivary testosterone in both groups after the W19 protocol (p < 0.05), but no such alteration was observed after W13. The testosterone response to the W19 protocol was significantly higher in young than in elderly men (p < 0.05). Although no modification on salivary cortisol was observed after either protocol, in young men, the cortisol response to W19 was higher than in elderly men (p < 0.05). Water-based exercise with emphasis on strength development was found to stimulate a more acute increase on salivary testosterone than water-based aerobic exercise, probably as a result of the higher intensity used in that training protocol. Given the known relationship between acute hormonal responses and chronic neuromuscular adaptations, the testosterone response after W19 should be considered when prescribing water-based exercise, especially to older populations. KEY WORDS water exercise, testosterone, cortisol, resistance training

Coingestion of D-pinitol with creatine (CR) has been reported to enhance creatine uptake. The purpose of this study was to evaluate whether adding D-pinitol to CR affects training adaptations, body composition, whole-body creatine retention, and/or blood safety markers when compared to CR ingestion alone after 4 weeks of resistance training. Twenty-four resistance trained males were randomly assigned in a doubleblind manner to creatine + pinitol (CRP) or creatine monohydrate (CR) prior to beginning a supervised 4-week resistance training program. Subjects ingested a typical loading phase (i.e., 20 g/[d.sup.-1] for 5 days) before ingesting 5 g/[d.sup.-1] the remaining 23 days. Performance measures were assessed at baseline (TO), week 1 (T1), and week 4 (T2) and included 1 repetition maximum (1RM) bench press (BP), 1RM leg press (LP), isokinetic knee extension, and a 30-second Wingate anaerobic capacity test. Fasting blood and body composition using dual-energy x-ray absorptiometry (DEXA) were determined at T1 and T3. Data were analyzed by repeated measures analysis of variance (ANOVA). Creatine retention increased (p < 0.001) in both groups as a result of supplementation but was not different between groups (p > 0.05). Significant improvements in upper- and lower-body strength and body composition occurred in both groups. However, significantly greater increases in lean mass and fat-free mass occurred in the CR group when compared to CRP (p < 0.05). Adding D-pinitol to creatine monohydrate does net appear to facilitate further physiological adaptations while resistance training. Creatine monohydrate supplementation helps to improve strength and body composition while resistance training. Data from this study assist in determining the potential role the addition of D-pinitot to creatine may aid in facilitating training adaptations to exercise. KEY WORDS supplements, exercise, performance, ergogenic, retention

The purpose of this study was to assess the effect of heavy/slow movements and variable resistance training on peak power and strength development. Forty-eight National Collegiate Athletic Association (NCAA) Division I athletes (age: 21.4 [+ or -] 2.1 years, all men) were recruited for this 12-week training intervention study. Maximum strength and jumping power were assessed before and after the training program. Athletes were randomly assigned to 1 of 3 training groups: heavy resistance/slow movement (Slow), lighter resistance and fast movement (Fast), or fast movements with accommodated resistance (FACC). All training groups performed similar training programs comprising free weight resistance training with lower-body compound exercises. The only difference among the training interventions was the speed at which subjects performed the squat exercise and the use of bands (Slow group: 0.2-0.4 meters/second; Fast group: 0.6-0.8 meters/second; FACC group trained 0.6-0.8 meters/ second with the addition of accommodated resistance in the form of large elastic bands). Post-test data revealed a significant difference between power improvements between the Slow and FACC groups (p = 0.02). Percent increases and effect sizes (ES) demonstrated a much greater treatment effect in the FACC group (17.8%, ES = 1.06) with the Fast group (11.0%, ES = 0.80) adapting more than the Slow group (4.8%, ES = 0.28). The FACC and Slow groups improved strength comparatively (FACC: 9.44%, ES = 1.10; Slow: 9.59%, ES = 1.08). The Fast group improved strength considerably less, 3.20% with an effect size of only 0.38. Variable resistance training with elastic bands appears to provide greater performance benefits with regard to peak force and peak power than heavy, slow resistance exercise. Sports conditioning professionals can utilize bands, and high-speed contractions, to increase power development. KEY WORDS power, speed, physical conditioning, sports conditioning

Resistance and endurance training are often performed concurrently in most exercise programs and in rehabilitative settings in an attempt to acquire gains in more than 1 physiologic system. However, it has been proposed that by simultaneously performing these 2 modes of exercise training, the strength gains achieved by resistance training alone may be impaired. Thus, the aim of this study was to compare the effects of 16 weeks of resistance training and concurrent resistance and endurance training on muscular strength development in 38 sedentary, apparently healthy males (25 yr [+ or -] 8 mo). Subjects were age-matched and randomly assigned to either a control (Con) group (n = 12), resistance training (Res) group (n = 13), or concurrent resistance and endurance training (Com) group (n = 13). After 16 weeks, no changes were found in the strength of the subjects in the Con group. Resistance training and concurrent resistance and endurance training significantly (p [less than or equal to] 0.05) improved strength in all of the 8 prescribed exercises. The data also indicated that 16 weeks of concurrent resistance training and endurance training was as effective in eliciting improvements in strength as resistance training alone in previously sedentary males. As such, concurrent resistance and endurance training does not impede muscular strength gains and can be prescribed simultaneously for the development of strength in sedentary, apparently healthy males and thus may invoke all the physiologic adaptations of resistance and endurance training at once. KEY WORDS Aerobic, combination, exercise, weight

Resistance sprint training is a sprint-specific training protocol commonly employed by athletes and coaches to enhance sprint performance. This research quantified the impact of lower extremity mass and inertia manipulation on key temporal and kinematic variables associated with sprint performance. A 3-dimensional analysis of 40 m sprinting was conducted on 8 elite sprinters under normal conditions and resisted sprint training. Results of the study showed that lower extremity additional mass training (at 10% individual segment weight) led to a significant reduction in sprint time for both the 10-m to 20-m and the 30-m to 40-m splits and the totar 40 m measure. The stride velocity throughout the 20-m to 30-m phase of the sprint trials was also shown to be significantly reduced in the lower extremity mass and inertia manipulation condition. Importantly, no significant differences were observed across the remaining spatiotemporal variables of stride length, stride frequency, total stride time, and ground contact time. For coaches and athletes, the addition of specific lower extremity mass could improve the athlete's sprint performance without any measured effect on the technique of highly trained elite sprinters. KEY WORDS resistance training, kinematics, performance enhancement

This study investigated the effects of body posture on systolic (SBP) and diastolic (DBP) blood pressure, mean arterial pressure (MAP), and heart rate (HR) after a session of resistance exercises. Twelve normotensive men were randomly assigned to either a control group (CG) or exercise group (EG). The EG performed 4 sets of 10 lifts at 80% of repetition maximum (10RM) using 4 different exercises. The BP and HR were assessed on different days in seated and supine postures at rest and at 10-minute intervals during 30 minutes of postexercise recovery. Except for DBP, a 3-way ANOVA revealed that postexercise SBP in EG was always lower than at rest during seated (minimum of 109.5 [+ or -] 1.4 mm Hg at 10 min vs. 119.2 [+ or -] 3.4 mm Hg at rest; p< 0.01) and supine recovery (minimum of 1 12.7 [+ or -] 3.0 mm Hg at 20 min vs. 118.4 [+ or -] 1.7 mm Hg at rest; p < 0.05). The MAP during recovery in the seated posture was lower than at rest (minimum 83.3 [+ or -] 2.6 mm Hg at 30 min vs. 89.3 [+ or -] 0.9 mm Hg at rest; p < 0.05), whereas in the supine posture, no difference was identified (minimum 83.6 [+ or -] 1.9 mm Hg at 10 min vs. 87.1 [+ or -] 1.8 mm Hg at rest; p > 0.05). The HR at 10 minutes (82.0 [+ or -] 4.8 bpm; p < 0.01), 20 minutes ([83.7 [+ or -] 6.3 bpm; p < 0.05), and 30 minutes (80.5 [+ or -] 6.2 bpm; p < 0.01 ) of recovery during the seated posture was higher than at rest (71.5 [+ or -] 2.1 bpm). In contrast, in the supine posture, HR was higher than at rest (66.8 [+ or -] 3.7 bpm; p < 0.01 ) throughout 10 minutes (79.7 [+ or -] 5.3 bpm) and 20 minutes of recovery (74.5 [+ or -] 4.2 bpm). In conclusion, the postexercise hypotensive response can be affected by posture during BP assessment. KEY WORDS strength, cardiovascular physiology, postexercise hypotension, training

The purpose of this study was to assess changes in upper-body muscular strength and work capacity following off-season resistance training and the resultant effect on prediction of muscular strength (1 repetition maximum, or 1 RM). National Collegiate Athletic Association (NCAA) Division II football players (n = 58) were divided into low-strength (LS, 1RM 85% 1RM) than at higher repetitions (>6RM, [less than or equal to] 80% 1RM) at both pre-and post-training. In conclusion, changes in muscular strength associated with the off-season training program used herein appear to have little effect on work capacity or prediction of 1RM using submaximal loads. For repetition predictions to accurately track changes following resistance training, the test load must be relatively high (>85% 1RM) and the repetitions low ([less than or equal to] 5 reps). KEY WORDS off-season conditioning, performance evaluation, bench press

This study examined the recovery of static and dynamic muscle performance after eccentric damage with and without repeated exercise, using different exercise modes between the initial and subsequent exercise bouts. Twelve nonweight-trained adults performed both control and repeated exercise conditions. Soreness, limb circumference, static joint angles, creatine kinase (CK), isometric strength, and dynamic muscle performance involving a stretch-shortening cycle (SSC) were monitored for 7 days to evaluate the recovery. After baseline measures, subjects performed 30 maximal isokinetic eccentric contractions (90 degrees/second) of the elbow flexors in each experiment. For the control condition, no treatment was applied. For the repeated exercise condition, 5 sets of arm curls using dumbbells (70% isometric maximal voluntary contraction of each testing day) were performed until failure on days 1, 2, 3, and 5 of recovery. Significant condition vs. time interactions existed in circumference (p = 0.012), static relaxed angle (p = 0.013), isometric strength (p = 0.039), and dynamic extension angle (p = 0.039), suggesting a slightly delayed onset of recovery with the repeated exercise. SSC performance changed more in parallel with soreness after eccentric exercise than did the other measures. It was concluded that the repeated bout effect was present, although slightly reduced, when subsequent exercise performed before recovery was intense and differed in mode from the initial eccentric exercise. Practical applications of this research are that resistance training may be continued after eccentric damage; however, a minor delay in the onset of recovery may occur depending on training modes. Muscle soreness is a good indicator of performance decrement during dynamic movements following eccentric damage. KEY WORDS DOMS, strength, stretch-shortening cycle, repeated bout effect

The objective of the study was to compare the effect of a 7-week unstable and stable resistance training program on measures of strength, balance, and functional performance. Forty participants were divided into unstable or stable resistance training groups. Training was conducted twice a week for 7 weeks. Pre- and post-testing measures included leg extension strength, static and dynamic balance, sit-ups, long jump, hopping test for time, shuttle run, and sprint. Results showed that there was no overall difference between unstable and stable resistance training and the training effects were independent of gender. All measures except sprint time improved with training. Interaction effects demonstrated that unstable resistance training did provide an advantage for number of sit-ups performed (p = 0.03; 8.9%) and the right leg hopping test (6.2%; p = 0.0001 ). This study has demonstrated that instability resistance training may be considered as effective as traditional stable resistance training for inexperienced resistance trainers. Based on the present study and the literature, instability resistance training should be incorporated in conjunction with traditional stable training to provide a greater variety of training experiences without sacrificing training benefits. KEY WORDS stability, sprint, shuttle run, static balance, dynamic balance

The purpose of this study was to examine the effects of a 6-week, periodized squat training program with (SQTV) or without (SOT) whole-body low-frequency vibration (WBLFV) on acute improvements in jump height and power output over 3 separate testing occasions. Participants ranged in age from 18 to 30 years and were randomized into 1 of 3 groups (CG, or control group, n = 6; SQTV, n = 13; or SOT, n = 11 ). SQTV and SOT performed Smith machine back squat training twice per week with 3 to 5 sets of 55 90O/o of the 1-repetition maximum (1RM). The SQTV group also received WBLFV (50 Hz; 2-6-mm amplitude) during the 6-week training period before training (30 seconds, 2-4-mm amplitude) and between sets (3 bouts lasting 10 seconds each). Two 30-cm depth jumps and two 20-kg squat jumps were performed after an acute vibration protocol during weeks 1,3, and 7. Jump height (cm), peak power (Pmax), peak power per kilogram of body mass (Pmax/kg), and mean power (Pav) were recorded for the depth and squat jumps. Although there were no group by trial interactions, percent change in Pmax for the squat jump was greater (p < 0.01) for the SQTV group than for the SQT group post WBLFV. In addition, the percent change scores for jump height and Pmax/kg for the depth jump were greater (p < 0.05) for SQTV than for SQT following WBLFV exposure. WBLFV during the 6-week squat training program resulted in greater acute improvements in power output and jump height for both jump conditions compared to SOT alone. KEY WORDS periodized resistance training, jump performance, post-activatiOn potentiation

The purpose of this study was to investigate the effect of concurrent resistance and endurance cycle training on physiologic and performance parameters of cyclists. Before and after a 6-week training intervention period, 14 well-trained male cyclists completed a maximal graded exercise test, a 30-km dynamic cycling test with 3 intermittent 250-m and 1 -km sprints, and a 1 repetition maximum (1 RM) squat test for the assessment of lower-limb strength. Subjects were allocated into 2 groups: a resistance training group (RT; n = 7) that completed a 6-week undulating, periodized resistance training program (3/wk) in conjunction with their regular cycle training and a control group (CON; n = 7) that maintained their usual cycle training. Upon completion of the training intervention, there was no change in graded exercise test parameters in either group, but the RT group showed a significantly greater increase in 1RM squat strength compared with CON (p < 0.05). Moreover, the change in 30-km time trial and sprinting performance did not differ between RT and CON, except for the final 1-km sprint where the percent change in 1-km final sprint performance was greater in CON (+11%) compared with RT (-5%). In conclusion, although concurrent resistance and endurance training in well-trained cyclists enhanced 1RM strength, it did not improve overall cycle time trial performance and in fact was shown to reduce 1-km final cycle sprint performance compared with a CON group performing their normal cycle training. KEY WORDS power output, sprinting, strength, athlete