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Adaptations to resistance training and subsequent performance can be undermined by inadequate interset recovery. Methods typically used to monitor recovery were developed for longitudinal use, making them time-inefficient within singular exercise bouts. If valid, perceptual recovery status (PRS) may be used as an efficient and inexpensive assessment tool to monitor individual recovery. Purpose: The aim of this study was to assess the validity of PRS on monitoring recovery during a high-intensity back-squat session. Methods: Ten healthy men participated in the 2-session study (separated by at least 48 h). Session 1 included anthropometrics, PRS familiarization, and a 1-repetition-maximum back squat. Session 2 included a high-intensity protocol (5 sets of 5 repetitions; 5-min interset recovery; 85% of 1-repetition maximum). PRS was obtained before the first set and during the last 30 seconds of each 5-minute recovery; rating of perceived exertion (RPE) was also collected. A linear position transducer collected mean barbell velocity (MBV). Repeated-measures correlations assessed the common intraindividual relationships of PRS scores to intraset MBV and RPE, respectively. Results: A very large, positive correlation appeared between PRS and MBV (r [95% CI] =.778 [.613 to.878]; P <.0001). A large, negative correlation emerged between PRS and RPE (r [95% CI] = −.549 [−.737 to −.282]; P <.001). Conclusions: Results indicate that PRS can be a means for practitioners to monitor individualized recovery. PRS tracked well with RPE, strengthening its utility in a practitioner-based setting. Findings provide insight into the practicality of PRS for recovery monitoring. It could be used alongside other measures (eg, MBV and countermovement jump) to individually program and maintain performance. [ABSTRACT FROM AUTHOR]

Introduction: Healthcare professionals are in an optimal position to deliver exercise information to pregnant women, yet previous research suggests this seldom happens. Midwives and nurse practitioners, who may have more time with pregnant women, are particularly well suited for this role. Objectives: This qualitative study examined the exercise advice and counseling provided by midwives and nurse practitioners in Kentucky, focusing on the barriers they face. Methods: Twenty-one midwives and nurse practitioners were recruited until the sample size reached saturation. A survey with open-ended questions was distributed to potential participants in regional hospitals, universities, and professional associations. The framework method was employed to identify common themes in the responses from participants. Results: Five main themes emerged: nature of advice, discussing exercise benefits, safety concerns, barriers to counseling, and suggestions for improvement. Findings revealed that midwives and nurse practitioners recommend moderate exercise, aiming for 150 min weekly, monitoring heart rate for intensity, continuing prepregnancy exercise routines, starting low-intensity exercise during pregnancy such as walking, slowing down as pregnancy advances, and avoiding heavy lifting and vigorous activities. Many midwives and nurse practitioners in our sample took a reactive approach to exercise counseling, providing exercise advice if pregnant women asked questions or if they were at high risk for hypokinetic diseases. It was also observed that midwives and nurse practitioners discussed the maternal benefits of exercise more than the fetal benefits. Only a few nurse practitioners and midwives were content with their counseling, while the majority did not feel their counseling was effective. Conclusions: Many midwives and nurse practitioners in Kentucky provided comprehensive and accurate physical activity guidelines to pregnant women. However, there is room for them to improve: proactive counseling should include discussions on fetal benefits and using the "talk test" for exercise intensity. Advising patients to slow down as pregnancy progresses should be reconsidered, and evidence-based guidance on specific exercises should be prioritized. [ABSTRACT FROM AUTHOR]

Aligning instructional modality with students' perceptual preference (PP) or learning style is trending in educational research. However, there is little data to support this claim when instruction is geared toward a recreational activity, such as fly casting. The purpose of this investigation was to evaluate the effects of implementing matched or unmatched instructional methods with student PP. There was no difference in casting performance between groups matched with their learning preferences versus those who were not matched. The data support Hanson's theory stating instruction should be dictated based on the content structure, not the learner's PP. The researchers recommend a systematic, multifaceted approach to teaching novel motor skills such as fly casting. Further, this approach could be utilized for similar motions in sport and recreation.

This study presents somatotype data on a team sport with chronic and diverse sporting demands. The aims were to (1) characterize a somatotype profile for Division II (DII) track and field athletes (n=54) by sex, class, and events; (2) determine if somatotype changed across the season; (3) determine if changes differed based on class or sex; and, (4) assess potential differences in somatotype between sexes. Methods: Anthropometrics (height, weight, body composition, somatotype) were evaluated after a competitive indoor season and immediately before the outdoor conference championships (41 days). Body measurements were assessed using a bioelectrical impedance analysis device, skinfold assessment, boney breadths, and limb girths. Descriptive statistics are provided as well as results from two-way ANOVAs which evaluate differences in actual and change scores across sex and class. Results: Our DII track and field athletes were primarily endomorphic (scores displayed as ENDO, MESO, ECTO, respectively). Males were found to be primarily ENDO-MESO somatotypes (4.7, 4.1, 3.0), while females were dominantly ENDO (7.7, 2.9, 2.9). Upperclass were more ENDO-MESO balanced compared with lowerclass (5.8, 3.8, 2.8 vs 6.0, 3.5, 3.0). When investigated based on sex, class level, and event, the groups were similar. There was no meaningful change to ECTO scores across the season for males or females. Female athletes improved ENDO scores (-0.89%) and males and females improved MESO scores (14.29% and 5.29%, respectively), indicating adaptations can be accomplished despite the chronic demands of a competitive season. Conclusion: Our research offers practitioners information about the potential changes they may expect across a competitive track and field season. [ABSTRACT FROM AUTHOR]

Although a variety of tools to monitor recovery have been developed, many are impractical for daily use due to cost, time, and challenges with interpretation. The Perceived Recovery Status (PRS) scale was recently developed as an expeditious, noninvasive tool to assess recovery status. While PRS has been strongly associated with repeated sprinting performance, a paucity of research exists relating PRS and performance recovery following resistance exercise. Purpose: The purpose of this study was to evaluate the sensitivity of PRS as a subjective marker of recovery up to 72 hours after a high-volume back-squat protocol. Methods: Eleven resistance-trained men reported to the laboratory on 5 separate occasions (1 familiarization session and 4 testing sessions). The first testing session was considered the baseline session and consisted of a nonfatiguing performance assessment (ie, countermovement jumps and back squats) and a fatiguing back-squat protocol of 8 sets of 10 at 70% 1-repetition maximum separated by 2 minutes of recovery. Participants returned 24, 48, and 72 hours following baseline to provide a PRS rating and complete the performance assessment. Results: Repeated-measures correlations revealed strong associations between PRS countermovement jump (r =.84) and mean bar velocity (r =.80) (both P <.001). Conclusions: The current findings suggest that PRS can be used as a method to effectively assess daily recovery following a fatiguing bout of resistance exercise. Practitioners are cautioned that the relationship between PRS and performance recovery is individualized, and equivalent PRS scores between individuals are not indicative of similar recovery. [ABSTRACT FROM AUTHOR]

The Bruce and Astrand treadmill protocols are commonly utilized when assessing maximal oxygen consumption (VO2max). However, the steep grade implemented in the protocols often leads to localized muscular fatigue, potentially causing participants prematurely to terminate the test prior to reaching their true VO2max. The purpose of this study was to evaluate a Novel VO2max protocol that may be better suited for young, apparently healthy populations. The Novel protocol starts at a higher speed and lower initial grade to limit lower extremity fatigue. Fifteen participants performed the Bruce, Astrand, and Novel protocols with the following maximal values recorded from each: VO2max, maximal ventilation (VEmax), respiratory exchange ratio (RER), heart rate (HR), rating of perceived exertion (RPE) and time to exhaustion (TTE). The Novel protocol displayed substantial agreement with both criterion protocols. Mean absolute percent error (MAPE) was less than 10% indicating that the Novel protocol is a valid measurement for VO2max values. Bland-Altman analysis revealed that the Novel protocol exhibited a low degree of bias, with tight limits of agreement when compared to the Bruce (bias ±95% LOA = 0.824 ± 3.163) and Astrand protocols (-0.153 ± 3.528) for VO2max. A paired samples t-test revealed no significant differences between Novel and criterion protocols for VO2max. Paired samples t-tests revealed that the Novel protocol had significantly lower TTE when compared to the Bruce and Astrand protocols and produced similar VO2max values to that of the Bruce and Astrand. The Novel protocol may be considered a valid and time-efficient protocol. [ABSTRACT FROM AUTHOR]

The purpose of this pilot study was to determine if there is a difference in metabolic cost when jumping on platforms of varying thickness, as well as whether a difference exists in metabolic cost between genders exists on the different platforms. Fourteen participants (seven males and seven females) completed three repetitive jumping trials on the DigiJump machine. Each trial was performed at a cadence of 120 jumps per minute and at a minimum height of 1/2" per jump. Trials were completed on platforms of 1/2", 3/8", and 1/4" thickness. Participants were instructed to jump as long as possible while maintaining the prescribed cadence or until fifteen minutes had elapsed. There were no differences observed in metabolic cost or exertion for all participants or between genders as indicated by oxygen consumption, respiratory exchange ratio, upper leg RPE, or lower leg RPE. There were also no differences for durations of exercise the participants were able to sustain on the machine. However, when comparing data between genders, a significant interaction was observed in total body RPE across the three platforms (p = .009) and in HR on the 1/2" platform (p = .018). Results from this study indicate that metabolic cost is similar during repetitive jumping regardless of platform rigidity or gender. However, post-trial comments from participants did show preferences towards specific platforms, though this was not apparent in exercise duration. [ABSTRACT FROM AUTHOR]

Context: Motorized treadmills (MTs) present an altered motor task compared to overground (OG) locomotion in that MT belt surfaces are motor-driven, whereas individuals walking/running OG must propel themselves. A possible solution may lie with novel nonmotorized treadmill (NMT) devices as the belt surface is propelled by the user. Objective: The purpose of this study was to compare gait performance during both MT and NMT locomotion to OG. Design: Crossover study. Setting: A university research laboratory. Patients: A total of 20 healthy adults (10 women) participated in the study. Intervention: Each participant performed self-selected walking and running OG, and on both an MT and NMT. Main Outcome Measure: Shoulder, trunk, and lower-extremity kinematics were analyzed for each treadmill condition and compared to OG. Results: The analyses demonstrated that there were no differences between MT and OG gait kinematics during either walking or running. However, NMT gait showed increased hip, knee, and ankle flexions in late swing and early stance compared to OG during both walking and running. For example, during walking, the NMT elicited hip-, knee-, and ankle-flexion/extension angles of 34.7°, 8.0°, and 3.6° at foot strike compared to 24.8°, −3.1°, and −5.8° in the OG condition (P <.05). There was also a significant reduction in trunk-flexion/extension range of motion during running compared to OG (7.7° in NMT vs 9.8° in OG). Conclusions: These differences may have implications for both training and rehabilitation on an NMT. Future studies should consider the influence of NMT familiarization on gait performance and should emphasize the assessment of neuromuscular performance. [ABSTRACT FROM AUTHOR]

The primary aim of this systematic review and meta-analysis was to quantify the magnitude of the effect of postactivation potentiation (PAP) on explosive vertical power while accounting for the nesting of multiple effects within each study. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Statement (PRISMA). Original research articles published by January 18, 2018, were located using an electronic search of 4 databases and yielded 759 original publications. Data were extracted and independently coded by 2 authors (W.C.D. and D.V.T.). The standardized mean effect size (ES) was calculated by subtracting the pre-treatment mean from the post-treatment mean and dividing by the pooled SD, adjusting for small sample bias. Multilevel random-effects model was used to aggregate a mean ES and 95% confidence interval (CI) for PAP on vertical jump performance. The cumulative results of 179 effects gathered from 36 studies indicate that PAP does not improve vertical jump performance (ES = 0.08, 95% CI -0.04 to 0.21, p = 0.197), with moderate heterogeneity. Moderator analysis indicated that rest intervals between 3 and 7 minutes provided favorable performance outcomes (ES = 0.18, 95% CI 0.05 to 0.31, p = 0.007). Conversely, rest intervals less than 3 minutes (ES = -0.15, 95% CI -0.31 to 0.01, p = 0.052) or performing isometric contractions (ES = -0.52, 95% CI -0.89 to -0.14, p = 0.007) may be detrimental to performance. Meta-regression indicated that rest interval was the only moderator significantly associated with ES (β = -0.04, 95% CI -0.57 to -0.02, R = 14.31%, p < 0.001). When appropriate PAP guidelines are followed, an increase in vertical jump performance may be achieved. [ABSTRACT FROM AUTHOR]

Rating of perceived exertion (RPE) extrapolation involves mathematically extending the submaximal relationship between RPE and oxygen consumption (VO2) to maximal intensity. This technique allows practitioners to forego, potentially dangerous, maximal exertion testing while attaining accurate measures of maximal oxygen consumption used for exercise prescription. This method has been proven accurate in adults, but much less in known when applied to an adolescent population. The purpose of this study was to assess the accuracy of the RPE extrapolation as method for estimating VO2max in adolescents. Twenty-two healthy, asymptomatic adolescents performed a graded exercise test (GXT) to exhaustion. Heart rate and VO2 were recorded throughout the bout with RPE being queried every two minutes using the Borg (6-20) RPE scale. Individual regression lines were fitted for each subject using RPE and VO2 for RPE values up to 13,15, and 17. Theoretical maximal RPE values of 20 and 19 were entered into the equation to calculate an estimated VO2max. Repeated measures ANOVA with planned contrasts showed that all VO2max estimation methods significantly overpredicted measured VO2max (p < .001). Error analysis via Bland-Altman plots revealed large limits of agreement between the all methods, indicating large variability in error between estimated and measured VO2max. The results suggest that submaximal RPE values using the Borg scale cannot be used to predict VO2max in children due to the amount of error in the prediction equations. These inaccuracies could lead to potential under or over-prescription of exercise intensity and adverse effects on the person's health. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine if heat exposure alters the measures of total body water (TBW), extracellular water (ECW), and intracellular water (ICW) in both single-frequency bioelectrical impedance analysis (BIA) and bioimpedance spectroscopy (BIS). Additionally, we sought to determine if any differences exist between the BIA and BIS techniques before and after brief exposure to heat. Body water was evaluated for twenty men (age=24±4 years) in a thermoneutral environment (22°C) before (PRE) and immediately after (POST) 15 min of passive heating (35°C) in an environmental chamber. The mean difference and 95% limits of agreement at PRE demonstrated that BIS yielded significantly higher body water values than BIA (all p<0.05; TBW=1.8kg; ECW=0.6±1.3kg; ICW=1.2±3.7kg). However, the effect size (ES) of the mean differences at PRE were small and the r-values were high (r≥0.97). TBW and ICW remained significantly higher at POST for BIS (both p<0.05; 1.4±3.2kg and 1.1±3.7kg, respectively) whereas ECW was not different (p>0.05; 0.2±1.5kg). Additionally, the ES of the mean differences at POST were trivial to small and the r-values were high (r≥0.96). When analyzing the changes in body water before and after heat exposure, POST values for BIS were significantly higher than PRE (all p<0.001; TBW=0.6±0.8kg; ECW=0.4±0.3kg; ICW=0.3±0.6kg). Similarly, POST values for BIA were significantly higher than PRE (all p<0.001; TBW=1.0±0.6kg; ECW=0.7±0.4kg; ICW=0.4±0.4kg). BIA and BIS provide similar body water estimates. However, the increase in POST body water values indicate more research is needed before either method can be used for estimating body water after heat exposure. [ABSTRACT FROM AUTHOR]

The article discusses a study regarding the influence of placebo effect on the performance of intermittent sprinting. Topics discussed include the difference in perceived recovery status (PRS) and perceived exertion (RPE), the influence of placebo in the recovery from sprinting, and the use of placebo in pain and fatigue mediation.

The Bruce and Astrand treadmill protocols are commonly utilized when assessing maximal oxygen consumption (VO 2max ). However, the steep grade implemented in the protocols often leads to localized muscular fatigue, potentially causing participants prematurely to terminate the test prior to reaching their true VO 2max . The purpose of this study was to evaluate a Novel VO 2max protocol that may be better suited for young, apparently healthy populations. The Novel protocol starts at a higher speed and lower initial grade to limit lower extremity fatigue. Fifteen participants performed the Bruce, Astrand, and Novel protocols with the following maximal values recorded from each: VO 2max , maximal ventilation (VE max ), respiratory exchange ratio (RER), heart rate (HR), rating of perceived exertion (RPE) and time to exhaustion (TTE). The Novel protocol displayed substantial agreement with both criterion protocols. Mean absolute percent error (MAPE) was less than 10% indicating that the Novel protocol is a valid measurement for VO 2max values. Bland-Altman analysis revealed that the Novel protocol exhibited a low degree of bias, with tight limits of agreement when compared to the Bruce (bias ±95% LOA = 0.824 ± 3.163) and Astrand protocols (-0.153 ± 3.528) for VO 2max . A paired samples t -test revealed no significant differences between Novel and criterion protocols for VO 2max . Paired samples t -tests revealed that the Novel protocol had significantly lower TTE when compared to the Bruce and Astrand protocols and produced similar VO 2max values to that of the Bruce and Astrand. The Novel protocol may be considered a valid and time-efficient protocol.

Cannabidiol (CBD) is a non-psychoactive cannabinoid purported to reduce symptoms of discomfort. Individuals are now using CBD to treat symptoms of multiple sclerosis, seizures, and chronic pain. Animal models indicate that CBD may be effective at reducing inflammation post fatiguing exercise. However, little evidence is available to evaluate these findings in humans. Therefore, the purpose of this investigation was to evaluate the impact of two doses of CBD oil on inflammation (IL-6), performance, and pain after an eccentric loading protocol. Participants ( n = 4) participated in three conditions (placebo, low dose, and high dose), in this randomized, counterbalanced design. Each condition took 72 hours to complete, with a 1-week washout period between conditions. At the beginning of each week, participants were subjected to a loading protocol of six sets of ten eccentric only repetitions in the single-arm bicep curl. Participants consumed capsules of either a placebo, low dose (2mg/kg) or high dose (10mg/kg) of CBD oil immediately following the session and continued every twelve hours for 48 hours. Venipunctures were taken before exercise and repeated at 24, 48, and 72 hours post exercise. Blood samples were centrifuged for 15 minutes in gel and lithium heparin vacutainers. Plasma was separated from cells and stored at -80° until analysis. Samples were analyzed using an immunometric assay for IL-6 (ELISA). Data were analyzed using a three (condition) by four (time) repeated measure ANOVA. There were no differences in inflammation between conditions (F(2,6) = 0.726, p = 0.522, n p 2 = 0.195) or across time (F(3,9) = 0.752, p = 0.548, n p 2 = 0.200), handgrip strength between conditions (F(2,6) = 0.542, p = 0.607, n p 2 = .153) or across time (F(3,9) = 2.235, p = .153, n p 2 = .427), or bicep curl strength between conditions (F(2,6) = 0.675, p = 0.554, n p 2 = .184) or across time (F(3,9) = 3.513, p = .150, n p 2 = .539). There were no differences in pain between conditions (F(2,6) = 0.495, p = 0.633, n p 2 = .142), but there was a difference across time (F(3,9) = 7.028, p = .010, n p 2 = .701). There were no significant interactions to note. Although there was no statistical significance between conditions (likely due to the low sample size), there was a visible increase in IL-6 48 (4.88 ± 6.53) and 72 hours (3.12 ± 4.26) post exercise in the placebo condition which was not observed in the low (48: 0.35 ± 2.22; 72: 1.34 ± 5.6) and high dose condition (48: 1.34 ± 1.34; 72: -0.79 ± 5.34). Future investigations should consider implementing eccentric resistance training across a larger portion of the body to improve ecological validity of the exercise. A larger sample would reduce risk of researchers committing a type II statistical error and give strength to detecting differences between conditions.

Studies have demonstrated that new and expectant mothers experience increased levels of stress and anxiety during the COVID-19 pandemic. Though prenatal yoga is an effective mode of improving mental health during pregnancy, no research has evaluated its effect on mental health during times of extreme stress, such as a global pandemic. The purpose of this study was to determine the influence of a single session and a 10-week prenatal yoga intervention on the mental health of pregnant women during the COVID-19 pandemic. Women ( n = 19; 28.52 ± 3.74 years; 20.94 ± 4.69 weeks gestation; BMI 29.33 ± 9.08) were randomized into a yoga or a non-yoga control group. There were no differences in demographic factors or depression/anxiety scores between groups at baseline. Baseline levels of anxiety and depression were high, with an average depression score of 8.10 ± 4.85 (scores > 8 represent possible depression) and an average anxiety score of 39.26 ± 12.99 (scores ≥ 39 represent a clinically significant anxiety). After just one session of yoga, women reported feeling less depressed ( p = 0.028), tense ( p < 0.001), and fatigued ( p = 0.004). After 10 weeks, the yoga group had lower anxiety ( p = 0.002), depression ( p = 0.032), and total mood disturbance ( p = 0.002) scores when compared to the control group. Yoga appears to benefit the mental health of expectant mothers, even in times of extreme stress. The findings of this study provide clinicians with valuable information regarding alternative exercise options for mental health during pregnancy during the COVID-19 pandemic.