Multi-Ingredient Preworkout Supplementation Compared With Caffeine and a Placebo Does Not Improve Repetitions to Failure in Resistance-Trained Women.

There has been an increase in the use of commercially available multi-ingredient preworkout supplements (MIPS); however, there are inconsistencies regarding the efficacy of MIPS in resistance-trained women. PURPOSE: To determine the effect of varying doses of MIPS compared with caffeine only (C) and a placebo (PL) on resistance-training performance in trained women. METHODS: Ten women (21.5 [2.3] y) completed 1-repetition-maximum tests at baseline for leg press and bench press. A within-group, double-blind, and randomized design was used to assign supplement drinks (ie, PL, C, MIPS half scoop [MIPS-H], and MIPS full scoop [MIPS-F]). Repetitions to failure were assessed at 75% and 80% to 85% of 1-repetition maximum for bench and leg press, respectively. Total performance volume was calculated as load × sets × repetitions for each session. Data were analyzed using a 1-way repeated-measures analysis of variance and reported as means and SDs. RESULTS: There were no differences in repetitions to failure for bench press (PL: 14.4 [3.2] repetitions, C: 14.4 [2.9] repetitions, MIPS-H: 14.2 [2.6] repetitions, MIPS-F: 15.1 [3.1] repetitions; P = .54) or leg press (PL: 13.9 [7.8] repetitions, C: 10.8 [5.9] repetitions, MIPS-H: 13.1 [7.1] repetitions, MIPS-F: 12.4 [10.7] repetitions; P = .44). Furthermore, there were no differences in total performance volume across supplements for bench press (PL: 911.2 [212.8] kg, C: 910.7 [205.5] kg, MIPS-H: 913.6 [249.3] kg, MIPS-F: 951.6 [289.6] kg; P = .39) or leg press (PL: 4318.4 [1633.6] kg, C: 3730.0 [1032.5] kg, MIPS-H: 4223.0 [1630.0] kg, MIPS-F: 4085.5 [2098.3] kg; P = .34). CONCLUSIONS: Overall, our findings suggest that caffeine and MIPS do not provide ergogenic benefits for resistance-trained women in delaying muscular failure.

Effects of Acute Exercise on Affect in Females with Substance Use Disorder.

Negative mood states experienced during the withdrawal stage of substance dependence have been associated with relapse in persons suffering from substance use disorder (SUD). Exercise is gaining attention as an adjunct therapy for SUD due to its ability to alleviate negative mood states experienced during withdrawal. The purpose of this study was to investigate the effects of acute, controlled bouts of aerobic and resistance exercise versus sedentary control (quiet reading) on positive affect (PA) and negative affect (NA) in females undergoing SUD treatment at inpatient facilities. Females (n=11; 34 ± 8 yrs) were randomly assigned to each condition in counterbalanced fashion. Aerobic exercise (AE) consisted of 20 minutes of steady-state moderate intensity (40-60% HRR) treadmill walking. Resistance exercise (RE) consisted of 20 minutes of standardized circuit weight training (1:1 work to rest ratio). The Positive and Negative Affect Scale (PANAS) was used to assess PA and NA pre- and post-interventions. Repeated measures ANOVAs indicated AE and RE significantly increased PA (p < 0.05) versus control, with no significant difference between AE and RE. Friedman's test revealed AE and RE significantly reduced NA (p < 0.05) versus control. Results indicate short bouts of aerobic and resistance exercise are equally effective for acute mood regulation and superior to a sedentary control in females undergoing inpatient SUD treatment.

Comparison of Acute Energy Expenditure and Rating of Perceived Exertion in Equivalent Bouts of Circuit Training and Treadmill Running.

ABSTRACT: Brewer, CB, Booher, BM, and Lawton, N. Comparison of acute energy expenditure and rating of perceived exertion in equivalent bouts of circuit training and treadmill running. J Strength Cond Res 35(3): 680-687, 2021-Circuit weight training (CT) maximizes exercise density, which may lead to an inaccurate perception of energy expenditure (EE). The purpose of this study was to compare acute EE indices and rating of perceived exertion (RPE) between CT and an equivalent bout of treadmill running (TR). College-aged men (n = 9) who regularly engaged in running and resistance training performed CT first. Circuit weight training that consisted of 10 resistance stations (40% of 1 repetition maximum, 15 repetitions, 60 b·min-1) was performed for 20 minutes. Heart rate (HR) and EE (Cosmed K4b2) were monitored continuously, and RPE was assessed consistently. A 20-min TR session was performed at the average HR maintained during CT. Dependent t-tests were used to assess differences in RPE, total EE (TEE, kcal), rate of EE (REE, kcal·min-1), and relative REE (RREE, kcal·kg-1·min-1) between CT and TR. Pearson's correlation was used to examine relationships between RPE and EE indices. Total EE was lower during CT (168.19 ± 16.42) than TR (244.20 ± 44.80); REE was lower during CT (8.49 ± 0.90) than TR (12.21 ± 2.24); and RREE was lower during CT (0.10 ± 0.02) than TR (0.15 ± 0.02) (all p < 0.001). Circuit weight training RPE (6.0 ± 1.1) was greater than TR (4.1 ± 0.6) (p < 0.001). There was no association between RPE and EE indices (p > 0.05). The average HR elicited by CT was 61% HR reserve. At equivalent HRs and duration, CT resulted in a significantly higher RPE but lower EE. It is imperative for subjects engaged in CT to understand that although CT results in HR values within an aerobic training zone and feels more strenuous, it is not associated with greater acute EE.

Resistance exercise and naproxen sodium: effects on a stable PGF2α metabolite and morphological adaptations of the upper body appendicular skeleton.

INTRODUCTION: Exercise-induced inflammation has been shown to be necessary for successful skeletal muscle regeneration post-injury. Accordingly, numerous investigations have demonstrated consequences of COX-inhibitors, anti-inflammatory drugs which prevent prostaglandin formation. In addition to its roles in inflammation, prostaglandin F2α (PGF2α) also mediates vital regenerative processes The majority of research to report consequences of suppressing inflammation has utilized acute injury models in combination with acute COX-inhibitor administration. To address the limited research investigating regular consumption of COX-inhibitors over time in exercising humans, the purpose of this study was to determine effects of a non-selective COX-inhibitor on a PGF2α metabolite and morphological adaptations of the upper body appendicular skeleton during periodized resistance training. Twenty-three (N = 23) recreationally trained college-aged males were randomly assigned to receive placebo (n = 11) or naproxen sodium (n = 12). Treatments were prophylactically administered in double-blind fashion with supervised upper body resistance exercise performed twice per week for 6 weeks. Venous blood was sampled pre- and post-exercise and analyzed for 13, 14-dihydro-15-keto PGF2α using enzyme immunoassay. Factorial mixed-design repeated-measures ANOVAs were utilized to examine relative changes in the plasma PGF2α metabolite and upper body appendicular morphology over the training period. RESULTS: Naproxen sodium significantly reduced the acute PGF2α metabolite response to exercise (p = 0.013); however, this effect diminished over time (p = 0.02), and both treatment groups exhibited significant increases in dominant arm skeletal muscle tissue (p = 0.037). CONCLUSION: Despite acute inhibition of the PGF2α metabolite at early time points, naproxen sodium did not hinder positive morphological adaptations of the upper body in response to resistance training.

Use of analgesics for exercise-associated pain: prevalence and predictors of use in recreationally trained college-aged students.

The objectives of this study were to examine the use of the analgesics for the relief of exercise-associated pain (EAP) and to examine personal and/or exercise characteristics that might potentially predict such use in recreationally trained college-aged individuals. Recreationally trained college-aged students (N = 263) were invited to complete a self-administered 16-item questionnaire concerning personal exercise habits and analgesic use for EAP. The primary dependent variable was analgesic use for EAP, and additional items sought to characterize patterns and behaviors related to the use. Descriptive statistics and frequencies were calculated for all items, and logistic regression was used to evaluate the ability of 4 variables to predict analgesic use for EAP: gender, length of time performing regular exercise, weekly frequency of aerobic exercise, and weekly frequency of resistance exercise. Approximately 36% of respondents reported analgesic use for EAP, with data indicating acute use for what is generally acute pain. With predictors considered individually, gender was a significant predictor, with female respondents being more likely to use analgesics for EAP (p = 0.04). With all predictors considered concurrently, the model did not significantly contribute to the prediction of use in this sample. Potential for misuse was highlighted by a large percentage of users who described themselves as very unlikely to follow label directions and more likely to take a dose exceeding recommendations. In light of research that reports a potential detriment to muscular regeneration when analgesics are consumed with exercise, it is important to be cognizant of the use of these drugs in individuals striving to improve muscular fitness. Coaches and trainers should educate athletes about the associated risks and caution those who may unnecessarily take analgesics.