Resistance Training Guidelines Research Articles

Movement pattern definitions for resistance training behavior measurement in diabetes.

Type 2 diabetes can result in debilitating vascular complications, and resistance training (RT) is an effective therapy for improving cardiovascular outcomes. However, only 10-30% of adults meet the public health guidance for RT. While current RT guidelines focus on targeting major muscle groups, guidance specific to simplified movement categorization may augment understanding of RT programming and improve uptake and outcomes. Current movement pattern definitions and descriptions lack clarity, accuracy, and consistency. This paper proposes movement definitions and descriptions to be used for RT intervention design and prescription, and includes the following categories: hip, knee, ankle, vertebral column, vertical push, horizontal push, vertical pull, and horizontal pull. These categories are intended to aid clinicians, researchers, and trainers in RT surveillance and RT intervention design for improving vascular complications in type 2 diabetes. Simplified RT program design using these categories may also facilitate greater RT program understanding and adherence for patients.

Task-specific resistance training adaptations in older adults: comparing traditional and functional exercise interventions.

Muscle strength declines ∼3% per year after the age of 70. Resistance training guidelines for older adults are often based on free-weight and machine exercises, which may be inaccessible and lack carryover to activities of daily living. We tested the hypothesis that resistance training adaptations in older adults are task-specific. Thirty adults (8 males, 22 females; mean age = 71 years) were randomly assigned to participate in 6weeks of supervised, high-intensity resistance training (twice per week) utilizing free-weight and machine exercises (traditional) versus functional activities that were overloaded with a weighted vest (functional). Participants were thoroughly familiarized with the exercises and testing prior to beginning the study. Major outcome measures included assessments of functional performance, five-repetition maximum strength, isometric knee extensor force, and quadriceps muscle size. Physical activity and nutrition were monitored. The study results demonstrate that the magnitude of improvement within a given outcome was largely dependent on group assignment, with greater improvements in gait speed and the timed-up-and-go in the functional group, but 2-3× greater five repetition maximum strength improvements for the trap bar deadlift, leg press, and leg extension following traditional resistance training. Both groups showed improvements in isometric knee extensor force and muscle size, suggesting that some aspects of the observed adaptations were generic, rather than specific. Overall, these novel findings suggest that, among older adults, 1) resistance training adaptations exhibit a high degree of task specificity and 2) significant improvements in functional outcomes can be achieved with the use of a weighted vest.

Associations Between Resistance Training and All-Cause Mortality: NHANES 1999-2006

Background: The Physical Activity Guidelines 2nd Edition recommends ≥2 days of resistance training (RT). Evidence supports a dose-response relation between RT volume and cardiometabolic health. We examined whether RT guidelines and volume were associated with lower all-cause mortality. Methods: Participants from the 1999-2006 NHANES cycles (N = 5855) self-reported the past 30 days of physical activity including the number of sessions, average session duration in minutes, and activity type. Mortality was ascertained from the linked National Death Index through the end of 2019. Cox proportional hazards regression was used to estimate hazard ratios for all-cause mortality by RT Guideline adherence and per 1000 MET-minutes of monthly RT volume. Results: Approximately 1-in-10 participants met the RT Guidelines (n = 612, 11.6%). The mean monthly RT volume was 2033.3 ± 2487.7 MET-minutes. Mortality incidence was 10.6% (n = 886). Neither meeting the Guidelines (HR [95% CI]; 1.02 [.74, 1.41], compared to not meeting the Guidelines) nor monthly RT volume per 1000 MET-minutes (1.02 [.92, 1.14]) was associated with all-cause mortality in adjusted models, with no evidence of effect modification by sex or age. Conclusions: The present study did not find an association between RT and all-cause mortality. These results do not support the RT canon, warranting further investigation.

Mechanisms of Behavior Change for a Digital Resistance Training Intervention: A Mediation Study

ABSTRACT Introduction/Purpose Few interventions that seek to enhance resistance training behavior examine the mechanisms through which they exert their effects. Rather, many trials focus on physiological outcomes under tightly controlled training regimens. Understanding how to promote resistance training in everyday life is vital. This study aimed to examine the mediators of a remote-based 9-wk randomized controlled trial with a 4-wk self-regulation intervention period. Methods Sixty-one participants 18–35 yr of age who were not currently achieving the American College of Sports Medicine resistance training guidelines received two Zoom-based personal training sessions, resistance training equipment, and access to a Web site with training videos. After the two personal training sessions, participants were randomized to an intervention or comparison condition. Participants in the intervention condition received four weekly Zoom-based coaching calls to discuss barriers and solutions to resistance training participation. Resistance training behavior participation, self-efficacy, intention, behavioral expectations, and coping planning were assessed after the intervention period and at a follow-up 4 wk later. A mediation analysis was conducted to examine if the intervention had indirect effects on behavior through changes in any of the measured psychological variables. Results All necessary measures were completed by 96.7% of participants. After the intervention, direct effects were observed on self-efficacy (b = 0.68, standard error (SE) = 0.26, P = 0.01), intention (b = 0.77, SE = 0.27, P = 0.004), coping planning (b = 0.43, SE = 0.13, P = 0.001), and behavioral expectations (b = 19.7, SE = 5.3, P = 0.0001). Self-efficacy (b = 2.07, SE = 0.83, P = 0.01) and intention (b = 3.0, SE = 0.61, P = 0.0001) had direct effects on behavior. In the multiple mediation model, intention emerged as a significant mediator (b = 2.64, SE = 0.83, P = 0.001). Conclusion These findings suggest that changes in intention contributed to changes in behavior. Techniques that target behavioral intention may be appropriate for in-home strength-training interventions in young adults.

Abstract P441: Association of Monthly Resistance Training Volume With All-Cause Mortality in NHANES 1999-2006

Introduction: The WHO Physical Activity Guidelines recommend at least 2 days of resistance training (RT) per week. RCTs have shown a dose-response between RT volume and improving blood pressure, lipids, and markers of glycemia. There is discordance between the Guidelines recommending a frequency while empirical evidence supports a volume. Our objective was to test whether RT Guidelines and volume were associated with lower mortality. Methods: Data are from the 1999–2006 NHANES cycles. Participants self-reported past 30 days of physical activity including type, which was used to assign METs, number of sessions, and average session duration in minutes. Those who reported engaging in RT (push-ups, sit-ups, and weightlifting) with no missing data were included ( N =1,391). RT volume was measured in monthly MET-minutes, calculated as the product of the number of sessions, mean session duration, and intensity. Mortality was ascertained from the linked National Death Index through the end of 2019. Covariates included monthly aerobic physical activity volume, sex, age, and education. Cox proportional hazards regression was used to estimate hazard ratios for all-cause mortality by RT Guideline adherence and RT volume. Results: Participants had a mean age of 41.3±16.3 years and were mostly male (62.7%). Most participants met the Guidelines ( n =1,041, 74.8%). The mean monthly RT volume was 2,210±2,550 MET-minutes. Mortality incidence was 11.4% with a mean follow-up time of 189±41.6 months (159 events, 263,585 total person-months). Neither meeting the Guidelines nor monthly RT volume was associated with all-cause mortality (Table 1.). There was no evidence of effect modification by sex or age. Conclusions: According to these findings, current Guidelines promoting RT for health benefits are not supported by empirical data. However, the absence of an association between monthly RT volume and all-cause mortality warrants further investigation using better instrumentation for assessing RT volume.

MHealth to Support Outdoor Gym Resistance Training: The ecofit Effectiveness RCT

In Australia, 45% of adults meet the aerobic recommendations, and only 9%-30% meet the resistance training guidelines. Given the lack of at-scale community-based interventions promoting resistance training, the aim of this study was to assess the impact of an innovative mHealth intervention on upper- and lower-body muscular fitness, cardiorespiratory fitness, physical activity, and social-cognitive mediators among a sample of community-dwelling adults. Researchers evaluated the community-based ecofit intervention using a cluster RCT from September 2019 to March 2022 in 2 regional municipalities of New South Wales, Australia. Researchers recruited a sample of 245 participants (72% female, aged 53.4±13.9 years) who were randomized to the ecofit intervention group (n=122) or waitlist control (n=123) group. The intervention group received access to a smartphone application with standardized workouts tailored to 12 outdoor gym locations and an introductory session. Participants were encouraged to perform at least 2 ecofit workouts per week. Primary and secondary outcomes were assessed at baseline, 3 months, and 9 months. The coprimary muscular fitness outcomes were evaluated using the 90-degree push-up and the 60-second sit-to-stand test. Intervention effects were estimated using linear mixed models accounting for group-level clustering (participants could enroll in groups of up to 4). Statistical analysis was conducted in April 2022. Statistically significant improvements were observed in upper (1.4 repetitions, 95% CI=0.3, 2.6, p=0.018) and lower (2.6 repetitions, 95% CI=0.4, 4.8, p=0.020) body muscular fitness at 9 months but not at 3 months. Increases in self-reported resistance training, resistance training self-efficacy, and implementation intention for resistance training were statistically significant at 3 and 9 months. This study has shown that a mHealth intervention promoting resistance training using the built environment can improve muscular fitness, physical activity behavior, and related cognitions in a community sample of adults. This trial was preregistered with the Australian and New Zealand Clinical Trial Registry (ACTRN12619000868189).

Is there a connection between individual thigh muscle volume and squat lifting velocity

Background
 Identifying key musculoskeletal and biomechanical criteria that are associated with Resistance Training (RT) is essential to avoid injury and optimise training outcome. Biomechanically, so-called velocity-based RT is an objective approach to directly quantify training intensity and effect. From a musculoskeletal perspective, RT enhances muscle force, which is correlated to the muscle’s physiological cross-sectional area, and thus muscle volume.
 Goal
 The goal of this study is to find out whether there exists a correlation between the change in lifting velocity during a squat set-to-exhaustion and the Hamstring to Quadriceps Muscle Volume Ratio (H/Q Ratio) as indicator of muscle strength.
 Methodology
 Ethical approval for this study was given by the Kantonale Ethikkommission Bern. Recreationally trained RT athletes (age 20-40years) were recruited through the investigator’s network. The methodology is divided into three parts. Firstly, the hamstring and quadriceps muscle volumes are determined using Magnetic Resonance Imaging (MRI) as gold standard. Thereby, the open-source software SASHIMI with an automatic tracking function is utilised to segment the MRI data. The segmented data is further processed with the Python programming language to derive the H/Q ratios. Secondly, lifting velocity during the squat is determined using data from optical motion capture (Vicon Nexus System with 10 infrared cameras) as gold standard. Thereby, a set-to-exhaustion is performed at 80% of each individual one repetition maximum (1RM), whereby the subjects are asked to complete the concentric phase at maximum speed to comply with velocity-based RT recommendations. Lifting velocity is derived from the tracked position of two reflective markers on the bar using the Python programming language. Thirdly, a statistical correlation analysis is conducted between the musculoskeletal and the biomechanical parameters. Statistical analysis is performed with the statistical analysis software R, with the level of significance set at p = 0.05.
 Results
 To date, MRI data have been acquired in five athletes and the corresponding muscle volumes have been determined (Quadriceps: 0.00525 +/-0.00185 m3 and Hamstrings: 0.0019 +/-0.007 m3). In addition, the load-velocity profiles have been derived in the same group of subjects. The MRI-based muscle volumes are in a similar range to previously published data (Maeo et al., 2021). Furthermore, the results of the load-velocity profiles show the anticipated decrease according to velocity-based RT guidelines (Rodriguez-Rosell et al., 2020).
 Discussion
 In a next step further data will be acquired in more subjects for subsequent statistical analysis. The outcome of the present study is expected to provide new scientific insights into the relationship between musculoskeletal and biomechanical criteria that affect squat performance. The insight may help to optimize velocity-based RT recommendations for individual athletes to maximise performance and reduce injury risks.
 References
 Rodríguez-Rosell, D., Yáñez-García, J. M., Sánchez-Medina, L., Mora-Custodio, R., & González-Badillo, J. J. (2020). Relationship between velocity loss and repetitions in Reserve in the bench press and back squat exercises. Journal of Strength and Conditioning Research, 34(9), 2537–2547. https://doi.org/10.1519/JSC.0000000000002881
 Maeo, S., Huang, M., Wu, Y., Sakurai, H., Kusagawa, Y., Sugiyama, T., Kanehisa, H., & Isaka, T. (2021). Greater hamstrings muscle hypertrophy but similar damage protection after training at long versus short muscle lengths. Medicine & Science in Sports & Exercise, 53(4), 825–837. https://doi.org/10.1249/MSS.0000000000002523

A multi-component, community-based outdoor gym intervention: the ecofit effectiveness trial

Introduction: In Australia, it is estimated that 45% of adults meet the aerobic training recommendations (i.e., 150-300 minutes of MVPA) and only 9-30% meet the resistance training (RT) guidelines (i.e., minimum 2 sessions/week). Given the lack of ‘scalable’ physical activity community-based interventions promoting RT, the aim of this effectiveness trial (based on the published ecofit efficacy trial) was to determine the effects of an innovative community-based multicomponent physical activity intervention promoting resistance and aerobic-based physical activity using outdoor gym equipment, smartphone technology, and social support.

Prescription of resistance training for sarcopenic older adults: Does it require specific attention?

Sarcopenia is an age-related neuromuscular disease characterized by substantial muscle atrophy, dynapenia and/or loss of physical function. Sarcopenia progression increases the risk for numerous negative events, including falls, disability, hospitalization, nursing home placement, and death. As such, this condition is recognized as an important topic in gerontology and geriatrics. The best approach to counteract the development and progression of sarcopenia is actively debated. Resistance training (RT) has received special attention in this context, owing to the large number of studies showing its ability to produce significant improvements in sarcopenia-related parameters. Recommendations to guide RT prescription for older adults with different conditions, including people who have traits of sarcopenia, have been published. Some authors have argued that RT guidelines for older adults are similar to one another, which may indicate that the presence of sarcopenia does not require specific physical exercise programs. However, older people with sarcopenia might present with peculiar physical, biomechanical, physiological, and psychosocial characteristics that, in our view, are not taken into adequate consideration in existing exercise guidelines. Here, we present evidence to support the view that RT prescription for older adults with sarcopenia is complex, multifactorial, and still needs more evidence.

Long-Term Time-Course of Strength Adaptation to Minimal Dose Resistance Training Through Retrospective Longitudinal Growth Modeling

ABSTRACTPublic health guidelines for resistance training emphasize a minimal effective dose intending for individuals to engage in these behaviors long term. However, few studies have adequately examined the longitudinal time-course of strength adaptations to resistance training. Purpose: The aim of this study was to examine the time-course of strength development from minimal-dose resistance training in a large sample through retrospective training records from a private international exercise company. Methods: Data were available for analysis from 14,690 participants (60% female; aged 48 ± 11 years) having undergone minimal-dose resistance training (1x/week, single sets to momentary failure of six exercises) up to 352 weeks (~6.8 years) in length. Linear-log growth models examined strength development over time allowing random intercepts and slopes by participant. Results: All models demonstrated a robust linear-log relationship with the first derivatives (i.e., changes in strength with time) trending asymptotically such that by ~1-2 years strength had practically reached a “plateau.” Sex, bodyweight, and age had minimal interaction effects. However, substantial strength gains were apparent; approximately ~30–50% gains over the first year reaching ~50–60% of baseline 6 years later. Conclusion: It is unclear if the “plateau” can be overcome through alternative approaches, or whether over the long-term strength gains differ. Considering this, our results support public health recommendations for minimal-dose resistance training for strength adaptations in adults.

Fast and ballistic contractions involve greater neuromuscular power production in older adults during resistance exercise

PurposeNeuromuscular power is critical for healthy ageing. Conventional older adult resistance training (RT) guidelines typically recommend lifting slowly (2-s; CONV), whereas fast/explosive contractions performed either non-ballistically (FAST-NB) or ballistically (FAST-B, attempting to throw the load) may involve greater acute power production, and could ultimately provide a greater chronic power adaptation stimulus. To compare the neuromechanics (power, force, velocity, and muscle activation) of different types of concentric isoinertial RT contractions in older adults.MethodsTwelve active older adult males completed three sessions, each randomly assigned to one type of concentric contraction (CONV or FAST-NB or FAST-B). Each session involved lifting a range of loads (20–80%1RM) using an instrumented isoinertial leg press dynamometer that measured power, force, and velocity. Muscle activation was assessed with surface electromyography (sEMG).ResultsPeak and mean power were markedly different, according to the concentric contraction explosive intent FAST-B > FAST-NB > CONV, with FAST-B producing substantially more power (+ 49 to 1172%, P ≤ 0.023), force (+ 10 to 136%, P < 0.05) and velocity (+ 55 to 483%, P ≤ 0.025) than CONV and FAST-NB contractions. Knee and hip extensor sEMG were typically higher during FAST-B than CON (all P < 0.02) and FAST-NB (≤ 50%1RM, P ≤ 0.001).ConclusionsFAST-B contractions produced markedly greater power, force, velocity and muscle activation across a range of loads than both CONV or FAST-NB and could provide a more potent RT stimulus for the chronic development of older adult power.

Potential Benefits of a Minimal Dose Eccentric Resistance Training Paradigm to Combat Sarcopenia and Age-Related Muscle and Physical Function Deficits in Older Adults.

The ability of older adults to perform activities of daily living is often limited by the ability to generate high mechanical outputs. Therefore, assessing and developing maximal neuromuscular capacity is essential for determining age-related risk for functional decline as well as the effectiveness of therapeutic interventions. Interventions designed to enhance neuromuscular capacities underpinning maximal mechanical outputs could positively impact functional performance in daily life. Unfortunately, < 10% of older adults meet the current resistance training guidelines. It has recently been proposed that a more “minimal dose” RT model may help engage a greater proportion of older adults, so that they may realize the benefits of RT. Eccentric exercise offers some promising qualities for such an approach due to its efficiency in overloading contractions that can induce substantial neuromuscular adaptations. When used in a minimal dose RT paradigm, eccentric-based RT may be a particularly promising approach for older adults that can efficiently improve muscle mass, strength, and functional performance. One approach that may lead to improved neuromuscular function capacities and overall health is through heightened exercise tolerance which would favor greater exercise participation in older adult populations. Therefore, our perspective article will discuss the implications of using a minimal dose, submaximal (i.e., low intensity) multi-joint eccentric resistance training paradigm as a potentially effective, and yet currently underutilized, means to efficiently improve neuromuscular capacities and function for older adults.

Minimal-Dose Resistance Training for Improving Muscle Mass, Strength, and Function: A Narrative Review of Current Evidence and Practical Considerations.

Resistance training (RT) is the only non-pharmacological intervention known to consistently improve, and therefore offset age-related declines in, skeletal muscle mass, strength, and power. RT is also associated with various health benefits that are underappreciated compared with the perceived benefits of aerobic-based exercise. For example, RT participation is associated with reduced all-cause and cancer-related mortality and reduced incidence of cardiovascular disease, hypertension, and symptoms of both anxiety and depression. Despite these benefits, participation in RT remains low, likely due to numerous factors including time constraints, a high-perceived difficulty, and limited access to facilities and equipment. Identification of RT strategies that limit barriers to participation may increase engagement in RT and subsequently improve population health outcomes. Across the lifespan, declines in strength and power occur up to eight times faster than the loss of muscle mass, and are more strongly associated with functional impairments and risks of morbidity and mortality. Strategies to maximise healthspan should therefore arguably focus more on improving or maintaining muscle strength and power than on increasing muscle mass per se. Accumulating evidence suggests that minimal doses of RT, characterised by lower session volumes than in traditional RT guidelines, together with either (1) higher training intensities/loads performed at lower frequencies (i.e. low-volume, high-load RT) or (2) lower training intensities/loads performed at higher frequencies and with minimal-to-no equipment (i.e. resistance 'exercise snacking'), can improve strength and functional ability in younger and older adults. Such minimal-dose approaches to RT have the potential to minimise various barriers to participation, and may have positive implications for the feasibility and scalability of RT. In addition, brief but frequent minimal-dose RT approaches (i.e. resistance 'exercise snacking') may provide additional benefits for interrupting sedentary behaviour patterns associated with increased cardiometabolic risk. Compared to traditional approaches, minimal-dose RT may also limit negative affective responses, such as increased discomfort and lowered enjoyment, both of which are associated with higher training volumes and may negatively influence exercise adherence. A number of practical factors, including the selection of exercises that target major muscle groups and challenge both balance and the stabilising musculature, may influence the effectiveness of minimal-dose RT on outcomes such as improved independence and quality-of-life in older adults. This narrative review aims to summarise the evidence for minimal-dose RT as a strategy for preserving muscle strength and functional ability across the lifespan, and to discuss practical models and considerations for the application of minimal-dose RT approaches.

Exercise Behaviors and Beliefs Among Pregnant Women in Rural Communities.

The purpose of this study is to examine beliefs and behaviors regarding exercise during pregnancy in pregnant and postpartum women living in rural communities. Surveys were distributed in healthcare settings and via social media to pregnant and postpartum (< 3months) women living in rural communities. Seventy-five women (28.1 ± 5.4year) participated. Nearly all believed light (96%) and moderate (89%) intensity exercise are safe to perform during pregnancy, while fewer agreed vigorous intensity (52%) or resistance (40%) exercise is safe. Most (88%) believed women can continue their exercise regimen, and 73% believed that previously inactive women can begin training while pregnant. Only one-third of women met recommendations for cardiorespiratory exercise. The majority (66%) never engaged in vigorous exercise, and most (73%) did not participate in resistance exercise. Pregnant women in rural communities participate in light intensity exercise, but are largely not meeting guidelines for aerobic or resistance training. Knowledge related to safe exercises, particularly resistance training, during pregnancy is limited. Targeted education and programmatic planning are needed in this population regarding exercise guidelines.

Resistance training and health in adults: an overview of systematic reviews.

The objective of this overview of systematic reviews was to determine the benefits and harms of resistance training (RT) on health outcomes in adults aged 18 years or older, compared with not participating in RT. Four electronic databases were searched in February 2019 for systematic reviews published in the past 10 years. Eligibility criteria were determined a priori for population (community dwelling adults), intervention (exclusively RT), comparator (no RT or different doses of RT), and health outcomes (critical: mortality, physical functioning, health-related quality of life, and adverse events; important: cardiovascular disease, type 2 diabetes mellitus, mental health, brain health, cognitive function, cancer, fall-related injuries or falls, and bone health). We selected 1 review per outcome and we used the GRADE process to assess the strength of evidence. We screened 2089 records and 375 full-text articles independently, in duplicate. Eleven systematic reviews were included, representing 364 primary studies and 382 627 unique participants. RT was associated with a reduction in all-cause mortality and cardiovascular disease incidence, and an improvement in physical functioning. Effects on health-related quality of life or cognitive function were less certain. Adverse events were not consistently monitored or reported in RT studies, but serious adverse events were not common. Systematic reviews for the remaining important health outcomes could not be identified. Overall, RT training improved health outcomes in adults and the benefits outweighed the harms. (PROSPERO registration no.: CRD42019121641.) Novelty This overview was required to inform whether there was new evidence to support changes to the recommended guidelines for resistance training.

COVID-19 — Is It Time for Exercise Clinicians to Prehabilitate “High Risk” Respiratory Patients?

COVID-19 — Is It Time for Exercise Clinicians to Prehabilitate “High Risk” Respiratory Patients?

Dynapenic Obesity: Strength, Body Composition, And Physical Function In Women Diagnosed With Breast Cancer

BACKGROUND: Breast cancer survivors (BCS) report more limitations performing activities requiring strength compared to women without a cancer history. Combined with obesity, BCS with dynapenia (poor muscle strength) may have greater risk of physical function (PF) difficulties; however, the prevalence and impact of dynapenic obesity (DO) in BCS remains unknown. PURPOSE: This study aimed to: 1) prospectively determine the prevalence of DO; 2) evaluate associations among DO, clinical factors, and resistance training (RT); and 3) determine if DO predicts PF in BCS from diagnosis to 2-year follow-up. METHODS: DO was operationalized as waist circumference (WC) ≥88 cm and poor grip strength, measured via dynamometry and categorized using ACSM normative values. RT participation was determined via interview and categorized as meeting/not meeting RT guidelines for cancer survivors. PF was self-reported as level of difficulty with tasks including standing in place, walking 2 blocks, and lifting objects. Assessments were conducted at diagnosis and repeated at 1- and 2-years post-surgery during scheduled oncology visits. Data were analyzed using descriptive statistics and linear regression. RESULTS: BCS (N=396, Mage=57.1±11.6 years, MBMI=29.2±6.2 kg/m2) had a mean WC of 96.2±17.6 cm and combined grip strength of 50.0±11.5 kg. The prevalence of DO was 18.3% at diagnosis, 28.2% at 1-year, and 34.5% at 2-year follow-up. DO was not associated with clinical factors (e.g., diagnosis stage, receipt of chemotherapy) at diagnosis. A weak, positive association between DO and age was observed at baseline (p=.009). Meeting RT guidelines at diagnosis was inversely associated with DO at baseline (p=.008) and 1-year (p=.05). Controlling for age and RT participation, DO at diagnosis significantly predicted PF difficulty at 1-year (β=.26, p=.007) and significantly predicted PF difficulty at 2-year follow-up (β=.15, p=.09). CONCLUSIONS: A significant proportion of BCS had high central adiposity and poor muscle strength from diagnosis to 1- and 2-year follow-up. DO significantly predicted PF difficulty after surgery, indicating the importance of strength and body composition prior to treatment. RT may be protective against DO; therefore, greater efforts to increase RT engagement in BCS are critically needed.

Progressive resistance training for adolescents with cerebral palsy: the STAR randomized controlled trial.

To evaluate the effect of progressive resistance training of the ankle plantarflexors on gait efficiency, activity, and participation in adolescents with cerebral palsy (CP). Sixty-four adolescents (10-19y; 27 females, 37 males; Gross Motor Function Classification System [GMFCS] levels I-III) were randomized to 30 sessions of resistance training (10 supervised and 20 unsupervised home sessions) over 10 weeks or usual care. The primary outcome was gait efficiency indicated by net nondimensional oxygen cost (NNcost). Secondary outcomes included physical activity, gross motor function, participation, muscle strength, muscle and tendon size, and muscle and tendon stiffness. Analysis was intention-to-treat. Median attendance at the 10 supervised sessions was 80% (range 40-100%). There was no between-group difference in NNcost at 10 (mean difference: 0.02, 95% confidence interval [CI] -0.07 to 0.11, p=0.696) or 22 weeks (mean difference: -0.08, 95% CI -0.18 to 0.03, p=0.158). There was also no evidence of between-group differences in secondary outcomes at 10 or 22 weeks. There were 123 adverse events reported by 27 participants in the resistance training group. We found that 10 supervised sessions and 20 home sessions of progressive resistance training of the ankle plantarflexors did not improve gait efficiency, muscle strength, activity, participation, or any biomechanical outcome among adolescents with CP. Thirty sessions of progressive resistance training of the ankle plantarflexors over 10 weeks did not improve gait efficiency among ambulatory adolescents with cerebral palsy. Resistance training did not improve muscle strength, activity, or participation. Ninety percent of participants experienced an adverse event. Most adverse events were expected and no serious adverse events were reported.

Functional Resistance Training and Affective Response in Female College-Age Students.

Although resistance training (RT) can lead to acute improvements in psychological, physiological and psychosocial outcomes, prevalence rates remain low in college-age females likely due to perceived barriers. This study compared the effects of an acute bout of both a functional RT (FRT) and traditional RT (TRT) session on affect, state anxiety enjoyment and physiological measures. Females (n = 34, mean age = 27 ± 4.5 yr) not currently meeting American College of Sports Medicine RT guidelines completed four sessions (2 FRT, 2 TRT) within 4 wk in a randomized crossover design. Session 1 familiarized participants to the RT exercises. Session 2 consisted of 2 × 10 moderate intensity repetitions. Outcome measures included affect and state anxiety (preexercise, postexercise, and 15 min postexercise); enjoyment (post), and manipulation measures of session RPE and HR). Between-condition comparisons indicate change scores in state anxiety pre- to post-15 (P = 0.028) and enjoyment levels post- (P = 0.02) were significantly greater in FRT than TRT. Within-condition analyses revealed pre- to post-15 changes in affect were positive and greater in FRT (d = 0.79) than TRT (d = 0.53, P = 0.47), and greater in decreases in state anxiety (FRT, d = -0.58; TRT, d = -0.37, P = 0.028). Mean session RPE was not significantly different between conditions (FRT 6 ± 1.2 units; TRT 6.3 ± 1.1 units; P = 0.11), though average percent of age-predicted maximum HR (FRT 68.7 ± 7.6; TRT 57.1 ± 8.4) was significantly different (P < 0.01). Findings suggest that compared with TRT, FRT is associated with higher acute positive psychological states, higher levels of enjoyment, and greater energy expenditure. Future studies are recommended to examine additional measures of affect and in-task timepoints to determine how these responses relate to maintenance and adherence, thereby potentially increasing the proportion of college females meeting American College of Sports Medicine RT and moderate-to-vigorous physical activity guidelines.

Exercise Training Guidelines for Multiple Sclerosis, Stroke, and Parkinson Disease: Rapid Review and Synthesis.

The translation of knowledge from exercise training research into the clinical management of multiple sclerosis, stroke, and Parkinson disease requires evidence-based guidelines that are uniformly recognizable by healthcare practitioners and patients/clients. This article synthesized resources that reported aerobic and resistance training guidelines for people with multiple sclerosis, stroke, and Parkinson disease. Systematic searches yielded 25 eligible resources from electronic databases and Web sites or textbooks of major organizations. Data were extracted (exercise frequency, intensity, time, and type) and synthesized into three sets of recommendations. Exercise guidelines for multiple sclerosis consistently recommended 2-3 d/wk of aerobic training (10-30 mins at moderate intensity) and 2-3 d/wk of resistance training (1-3 sets between 8 and 15 repetition maximum). Exercise guidelines for stroke recommended 3-5 d/wk of aerobic training (20-40 mins at moderate intensity) and 2-3 d/wk of resistance training (1-3 sets of 8-15 repetitions between 30% and 50% 1 repetition maximum). Exercise guidelines for Parkinson disease recommended 3-5 d/wk of aerobic training (20-60 mins at moderate intensity) and 2-3 d/wk of resistance training (1-3 sets of 8-12 repetitions between 40% and 50% of 1 repetition maximum). This harmonization of exercise guidelines provides a prescriptive basis for healthcare providers, exercise professionals, and people with multiple sclerosis, stroke, and Parkinson disease regarding exercise programming.