We investigated the effects of different weekly-set progressions on perceptual responses and explored whether muscle thickness (MT) responses were related to perceptual and volume metrics in resistance-trained males. Thirty-one participants were randomly assigned to one of the three groups: a fixed set (FS) group (n = 10), maintaining 22 weekly quadriceps sets; a 4-Set (4S) group (n = 10) and a 6-Set (6S) group (n = 11), increasing by four and six every fortnight, respectively. Training occurred twice weekly for 12 weeks. The session rating of perceived exertion (sRPE) and session feelings of pleasure/displeasure (sFPD) were assessed 15 min post-training, while sRPE-derived metrics (monotony and strain) were analyzed weekly. The sRPE was higher in the FS compared to the 4S group (p = 0.046), while sFPD were higher in the FS compared to the 6S group (p < 0.001). Monotony was lower in the 4S than in other groups (p < 0.001). Strain followed a graded dose-response (6S > 4S > FS, p < 0.001). Overall, there were no meaningful correlations between volume load slopes and MT (r < 0.392) or perceptual responses (r < 0.448). These findings suggest that progressive increases in weekly-set volume influence perceptual responses; however, these responses do not appear to be related to changes in muscle thickness.
Purpose Resistance training using different ranges of motion may produce varying effects on musclular adaptations. The purpose of this study was to compare the effects of lengthened partial repetitions (LPs) vs. full range of motion (ROM) resistance training (RT) on muscular adaptations. Methods In this within-participant study, thirty healthy, resistance-trained participants had their upper extremities randomly assigned to either a lengthened partial or full ROM condition; all other training variables were equivalent between limbs. The RT intervention was an 8-week program targeting upper-body musculature. Training consisted of two training sessions per week, with four exercises per session and four sets per exercise. Muscle hypertrophy of the elbow flexors and elbow extensors was evaluated using B-mode ultrasonography at 45% and 55% of humeral length. Muscle strength-endurance was assessed using a 10-repetition-maximum test on the lat pulldown exercise, both with a partial and full ROM. Data analysis employed a Bayesian framework with inferences made from posterior distributions and the strength of evidence for the existence of a difference through Bayes factors. Results Both muscle thickness and unilateral lat pulldown 10-repetition-maximum improvements were similar between the two conditions. Results were consistent across outcomes with point estimates close to zero, and Bayes factors (0.16 to 0.3) generally providing “moderate” support for the null hypothesis of equal improvement across interventions. Conclusions Trainees seeking to maximize muscle size should likely emphasize the stretched position, either by using a full ROM or LPs during upper-body resistance training. For muscle strength-endurance, our findings suggest that LPs and full ROM elicit similar adaptations.
Introduction/PurposeThis study compared the effects of single-set resistance training performed with maximal effort (failure) versus submaximal effort on muscular adaptations.MethodsForty-two young, resistance-trained men and women were randomly assigned to one of two parallel groups: a group that trained to failure on all exercises (FAIL) or a submaximal effort group (2-RIR) that trained with two repetitions in reserve for the same exercises. Participants performed a single set of nine exercises targeting all major muscle groups per session, twice weekly for 8 wk. We assessed pre-post study changes in muscle thickness for the biceps brachii, triceps brachii, and quadriceps femoris, along with measures of muscular strength, power, endurance, and ability to estimate RIR in the bench press and squat.ResultsResults indicated that both FAIL and 2-RIR elicited appreciable gains in most of the assessed outcomes. Several measures of hypertrophy tended to favor FAIL, although absolute differences between conditions were generally modest. Increases in countermovement jump height favored FAIL, but with no clear statistical support for either the null or alternative hypothesis. Increases in strength and local muscular endurance were similar between conditions. Participants demonstrated greater accuracy in estimating RIR for the bench press compared with the squat and improved their accuracy over the intervention, particularly for the bench press.ConclusionsThese findings suggest that single-set routines can be a time-efficient strategy for promoting muscular adaptations in resistance-trained individuals, even when transitioning from higher-volume programs. Training to failure in single-set routines may modestly enhance some measures of muscle hypertrophy and power, but not strength or local muscle endurance.
Exercise technique, defined as the controlled execution of bodily movements to ensure an exercise effectively targets specific muscle groups while minimizing the risk of injury, is a resistance training (RT) variable frequently highlighted as critical to successful RT program outcomes, with proper technique suggested to play a role in maximizing muscle development. This study examined the effects of externally applied momentum on RT-induced muscular adaptations in the upper extremities. Thirty young adults were recruited to participate in a within-participant design, with one limb randomly allocated to perform biceps curls and triceps pushdowns using strict form (STRICT) and the other using external momentum (CHEAT). Participants completed four sets of each exercise with 8-12 repetitions until momentary muscular failure, twice a week for eight weeks. We obtained pre-post proximal and distal measures of muscle thickness for the elbow flexors and extensors, and assessed circumference changes in the upper arms. Data were analyzed in a Bayesian framework including both univariate and multivariate mixed effect models with random effects. Differences between conditions were estimated as average treatment effects, with inferences based on posterior distributions and Bayes Factors (BFs). Results showed similar between-conditions increases for all muscle thickness sites as well as circumference measures, generating consistent support for the null hypothesis (BF = 0.06 to 0.61). Volume load was markedly greater for CHEAT compared to STRICT across each week of the intervention. In conclusion, the use of external momentum during single-joint RT of the upper extremities neither helped nor hindered hypertrophy of the target muscles.
The purpose of this paper was to systematically review the literature and perform a meta-analysis of the existing data on the effects of postexercise cold water immersion (CWI) coupled with resistance training (RT) on gains in measures of muscle growth. To locate relevant studies, we comprehensively searched the PubMed/MEDLINE, Scopus, and Web of Science databases. A total of 8 studies met the inclusion criteria; all investigated CWI as the means of cold application. Preliminary analyses conducted on noncontrolled effect sizes provided strong evidence of hypertrophic adaptations with RT that were likely to be at least small in magnitude (SMD0.5 = 0.36 [95% CrI: 0.10-0.61]; p (>0) = 0.995, p (>0.1) = 0.977). In contrast, noncontrolled effect sizes provided some evidence of hypertrophic adaptations with CWI + RT that were likely to be small to negligible in magnitude (SMD0.5 = 0.14 [95% CrI: -0.08-0.36]; p (>0) = 0.906, p (>0.1) = 0.68). The primary analysis conducted on comparative effect sizes provided some evidence of greater relative hypertrophic adaptations with RT compared to CWI + RT (cSMD(0.5) = -0.22 [95% CrI: -0.47 to 0.04]) with differences likely to be greater than zero (p (<0) = 0.957) and of at least a small magnitude of effect (p (<-0.1) = 0.834). Meta-regression did not indicate a potential moderation effect of training status ( = -0.10 [95% CrI: -0.65 to 0.43] p < 0) = 0.653). In conclusion, based on the current data, the application of CWI immediately following bouts of RT may attenuate hypertrophic changes. Given the overall relatively fair to poor quality of the studies examined, the results of the current study should be interpreted with some caution.
This study assessed a male competitive powerlifter over a 6-month period that encompassed his pre-contest preparation and post-contest recovery. We conducted the following monthly assessments: multi-frequency bioelectrical impedance analysis (MF-BIA), B-mode ultrasound evaluation of muscle thickness (MT), body circumferences, handgrip strength, vertical jump height, isometric lower body strength, and questionnaires for perceived mood and sleep. The athlete undertook a 3-month pre-contest preparatory period that included an extreme energy-restricted diet intended to sufficiently reduce body mass. This period also included an 8-week pre-contest training regimen with a 10-day taper intended to promote peak strength increases in the target lifts for competition. During the pre-competition period, the athlete experienced rapid and substantial losses of body mass (10.3%), body fat (6.5%) and lean mass (3.3%), the majority of which was regained in the 2-month post-competition recovery phase. The athlete's isometric knee extension strength rose sharply during the initial month of the pre-competition phase (336.4 Nm), followed by consistent declines (299 to 262.2 to 283 Nm) over the next 3 months, eventually returning close to baseline values 2 months post- competition Jump height remained steady in the 3 months in the pre-contest phase but increased (+1.4 cm) in the 2 months post-competition while handgrip strength increased during the months preceding the competition (47.5 kg to 49 kg) but decreased to 42.3 cm post-competition. Overall, the athlete did not seem to have any marked sleep disturbances. The most notable changes in mood parameters were increased tension, anger, and depression immediately preceding the competition.
This study had 2 primary aims (1) compare the effects of multi-joint vs. single-joint lower body exercise on regional muscular development of the quadriceps; and (2) compare the effects of exercises performed at different knee-joint angles on hypertrophy of the triceps surae. Thirty young, resistance-trained participants unilaterally performed a combination of the following lower body exercises: leg press, leg extension, straight-leg toe press, and seated calf raise. The participants’ right legs were randomly allocated to perform 1 of the following 4 conditions: (1) leg press and straight-leg toe press; (2) leg-press and seated calf raise; (3) leg extension and straight-leg toe press; (4) leg extension and seated calf raise. Based on the allocated condition, the contralateral leg performed the other 2 exercises included in the protocol. Training was carried out twice per week on non-consecutive days for 8 weeks. Point estimates for the rectus femoris outcomes favored the single-joint exercise intervention with posterior probabilities ranging from 0.910 ≤ P ≤ 0.990. In contrast, point estimates for the vastus lateralis outcomes favored the multi-joint exercise intervention with posterior probabilities ranging from 0.875 ≤ P ≤ 0.994. Regarding the triceps surae, the point estimate favored straight-leg plantar flexion for muscle thickness of the medial gastrocnemius (P = 0.991), with equivocal results observed for the lateral gastrocnemius and soleus. Our findings indicate that exercise selection can influence regional hypertrophy of the muscles of the lower limbs and evidence of differences can be measured within 8 weeks.
The purpose of this paper was to carry out a systematic review with a meta-analysis of randomized controlled trials that examined the combined effects of resistance training (RT) and creatine supplementation on regional changes in muscle mass, with direct imaging measures of hypertrophy. Moreover, we performed regression analyses to determine the potential influence of covariates. We included trials that had a duration of at least 6 weeks and examined the combined effects of creatine supplementation and RT on site-specific direct measures of hypertrophy (magnetic resonance imaging (MRI), computed tomography (CT), or ultrasound) in healthy adults. A total of 44 outcomes were analyzed across 10 studies that met the inclusion criteria. A univariate analysis of all the standardized outcomes showed a pooled mean estimate of 0.11 (95% Credible Interval (CrI): −0.02 to 0.25), providing evidence for a very small effect favoring creatine supplementation when combined with RT compared to RT and a placebo. Multivariate analyses found similar small benefits for the combination of creatine supplementation and RT on changes in the upper and lower body muscle thickness (0.10–0.16 cm). Analyses of the moderating effects indicated a small superior benefit for creatine supplementation in younger compared to older adults (0.17 (95%CrI: −0.09 to 0.45)). In conclusion, the results suggest that creatine supplementation combined with RT promotes a small increase in the direct measures of skeletal muscle hypertrophy in both the upper and lower body.
The present paper aimed to systematically review case studies on physique athletes to evaluate longitudinal changes in measures of body composition, neuromuscular performance, chronic hormonal levels, physiological adaptations, and psychometric outcomes during pre-contest preparation. We included studies that (1) were classified as case studies involving physique athletes during the pre-contest phase of their competitive cycle; (2) involved adults (18+ years of age) as participants; (3) were published in an English-language peer-reviewed journal; (4) had a pre-contest duration of at least 3 months; (5) reported changes across contest preparation relating to measures of body composition (fat mass, lean mass, and bone mineral density), neuromuscular performance (strength and power), chronic hormonal levels (testosterone, estrogen, cortisol, leptin, and ghrelin), physiological adaptations (maximal aerobic capacity, resting energy expenditure, heart rate, blood pressure, menstrual function, and sleep quality), and/or psychometric outcomes (mood states and food desire). Our review ultimately included 11 case studies comprising 15 ostensibly drug-free athletes (male = 8, female = 7) who competed in various physique-oriented divisions including bodybuilding, figure, and bikini. The results indicated marked alterations across the array of analyzed outcomes, sometimes with high inter-individual variability and divergent sex-specific responses. The complexities and implications of these findings are discussed herein.