High-velocity Resistance Training Research Articles

Effects of High-Velocity Versus Low-Velocity Resistance Training on Muscle Echo Intensity in Healthy Young Women: A Randomized Controlled Trial.

Improving muscle quality to prevent and treat muscle dysfunction is critical. However, effective measures to improve muscle quality remain poorly understood. We investigated the effects of high- and low-velocity resistance training (RT) on muscle quality, mass, and function before and after an 8-week intervention. High-velocity RT would improve muscle quality more effectively than low-velocity RT. Randomized controlled trial. Level 1. A total of 33 healthy young women (23.1 ± 2.2 years) were assigned randomly to high-velocity (n = 16) or low-velocity (n = 17) groups. Both groups underwent concentric knee extension RT with a 60% 1-repetition maximum (1RM) load, performing 10 repetitions of 4 sets, 3 times per week for 8 weeks. The high-velocity group was instructed to complete each repetition as quickly as possible (mean repetition duration of 0.5 seconds), while the low-velocity group was required to execute each repetition in 3 seconds. Before and after the 8-week intervention, quadriceps femoris echo intensity (EI), muscle thickness (MT), isokinetic peak torque (60 and 300 deg/s), rate of velocity development (RVD) at 300 deg/s, and 1RM were assessed. Split-plot factorial design analysis of variance was used to compare the group × time interaction. A group×time interaction was observed for EI (P < 0.01). Only the high-velocity group showed a significant reduction in EI after the intervention. MT revealed a main effect of time (P < 0.01), with both groups significantly increasing MT. RVD showed a group × time interaction (P < 0.05), with significant increase only in the high-velocity group. Isokinetic peak torque and 1RM showed main effects of time (P < 0.01), with significant increases in both groups. High-velocity RT may be superior to low-velocity RT in enhancing muscle quality and RVD. These results emphasize the importance of RT velocity for muscle quality improvement.

High-velocity resistance training improves executive function in mobility-limited older adults

ObjectivesTo examine the effect of high-velocity resistance training (HVRT) on the executive function of middle-aged and older adults with and without mobility limitations. MethodsParticipants (n = 41, female: 48.9%) completed a supervised 12-week HVRT intervention (2 sessions/week; at 40–60% of one-repetition maximum). The sample included 17 middle-aged adults (40–55 years); 16 older adults (>60 years) and 8 mobility-limited older adults (LIM). Executive function was assessed before and after the intervention period and was reported as z-scores. Maximal dynamic strength, peak power, quadriceps muscle thickness, maximal isometric voluntary contraction (MVIC), and functional performance were also measured pre and post intervention. Training-related adaptations in cognitive measures were calculated using a Generalized Estimating Equation model. ResultsHVRT improved executive function in LIM (adjusted marginal mean differences [AMMD]: 0.21; 95%CI: 0.04, 0.38; p = 0.040) although no effect on middle-aged (AMMD: 0.04; 95%CI: -0.09; 0.17; p = 0.533) and older (AMMD: -0.11; 95%CI: -0.25; 0.02; p = 0.107) participants was observed. Improvements in maximal dynamic strength, peak power, MVIC, quadriceps muscle thickness, and functional performance were all associated with changes in executive function, and changes in the first four also seem to mediate the association between changes in functional performance and executive function. ConclusionsHVRT-induced improvement in executive function of mobility-limited older adults were mediated by changes in lower-body muscle strength, power, and muscle thickness. Our findings reinforce the relevance of muscle-strengthening exercises to preserve cognition and mobility in older adults.

High-velocity resistance training mitigates physiological and functional impairments in middle-aged and older adults with and without mobility-limitation.

The aim of the present study was to compare the neuromuscular, morphological, and functional responses to a high-velocity resistance training (HVRT) program between three cohorts: middle-aged adults (40–55 years, n = 18), healthy older adults (> 60 years, n = 18), and mobility-limited older adults (n = 8). Participants were tested before and after a 4-week control period and then assigned to a 12-week HVRT intervention. Investigated outcomes included ultrasound-derived muscle thickness and quality, maximal dynamic strength (1RM), maximal voluntary isometric contraction (MVIC), and muscle activation (sEMG), as well as muscle power and functional performance. After the intervention, quadriceps muscle thickness, 1RM, and sEMG improved in all three groups (all p < 0.05), whereas muscle quality improved only in middle-aged and older participants (p ≤ 0.001), and MVIC only in middle-aged and mobility-limited older adults (p < 0.05). With a few exceptions, peak power improved in all groups from 30–90% 1RM (p < 0.05) both when tested relative to pre-training or post-training 1RM workloads (all p < 0.05). Both mobility-limited older adults and older adults improved their short physical performance battery score (p < 0.05). Chair stand, stair climb, maximal gait speed, and timed up-and-go performance, on the other hand, improved in all three groups (p < 0.05), but no change was observed for habitual gait speed and 6-min walk test performance. Overall, our results demonstrate that a HVRT intervention can build a stronger foundation in middle-aged individuals so that they can better deal with age-related impairments at the same time that it can mitigate already present physiological and functional impairments in older adults with and without mobility-limitation.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11357-022-00520-8.

Metformin Impairs the Cardiorespiratory Fitness Adaptation to High-Intensity Power Training in Older Adults With Type 2 Diabetes: Results From the GREAT2DO Randomised Controlled Trial

Cardiorespiratory fitness (CRF) is a strong, modifiable predictor of cardiovascular mortality in type 2 diabetes (T2D). Metformin is commonly prescribed for T2D management and is known to impair CRF adaptations to aerobic training, however its effect on CRF adaptations to high-intensity, high velocity resistance training (Power training; POWER) has never been studied.

High Intensity Power Training Improves Ambulatory Blood Pressure for Hypertensive Older Adults With Type 2 Diabetes: Results From the GREAT2DO Randomised Controlled Trial

Hypertension is a cardiovascular disease (CVD) risk factor modifiable by exercise. The chronic effect of high-intensity, high-velocity resistance training (Power Training; POWER) on ambulatory blood pressure (ABP) in older adults with type 2 diabetes (T2D) is unknown.

High-velocity resistance training as a tool to improve functional performance and muscle power in older adults.

The aging process results in several physiological impairments that, in turn, may predispose older individuals to a series of restrictions on their functional capacity. These impairments are important to understand so that suitable conditions for healthier aging can be pursued. In this review, we first summarize the effects of aging on the neuromuscular system, as well as on the relation between the main age-associated physiological impairments and functional performance with an emphasis on muscle power output. We then proceed to discuss the effects of resistance training, specifically high-velocity resistance training (HVRT), on the aforementioned neuromuscular impairments, and on functional performance in healthy and mobility-limited older adults. Collectively, available evidence suggests that HVRT seems to be a safe and effective intervention for improving muscle power, functional performance, and mobility of older individuals. It also seems that mobility-limited older adults may improve power and functional performance to a greater extent than their healthy counterparts after HVRT, which is in line with the principle of diminishing returns. Considering that only a very limited number of investigations directly compared the effects of HVRT in more than one of the aforementioned groups, studies comparing the adaptations to HVRT of middle-aged adults and older adults with distinct functional capacities would be valuable to determine whether there are differences in neuromuscular adaptations, functional performance, and functional reserve among these groups.

Effects of High Intensity Exercise during Early Postmenopause-the Randomized Controlled ACTLIFE-Study

The aim of the study was to determine the effect of a dedicated exercise program on important menopausal risk factors and complaints in osteopenic early-postmenopausal women. Fifty-four women, 1-5 years postmenopause with osteopenia were randomly assigned (a) to a high impact weight bearing/high intensity, high velocity resistance training group (EG: n=27) exercising three times a week or (b) to an attention control group (CG: n=27). Study endpoints were body composition including Bone Mineral Density (BMD) at the Lumbar Spine (LS) as determined by Dual-Energy X-Ray Absorptiometry (DXA), menopausal symptoms, low back pain, lower extremity strength and power. After 28 weeks of intervention, significant effects were determined for free fat mass (EG: 0.48±0.68 kg vs CG: -0.15±0.88 kg, standardized mean differences (SMD): 0.80, p=.005), total body fat mass (EG: -1.19±1.26 kg vs CG: 0.36±1.59 kg,SMD: 1.08, p=.001), abdominal body fat rate (-1.26±1.99% vs 0.54± 1.53%, SMD: 1.02, p=.001), low back pain frequency (SMD: 0.55, p=.049) and severity (SMS: 0.66, p=.018), lower extremity strength (SMD: 1.46, p<.001) and jumping height (SMD: 0.92, p<.001) in the EG compared with the CG. Menopausal complaints improved in both groups, but changes were only significant in the EG (SMD: 0.33, p=.232). We did not determine significant exercise effects on LS-BMD (SMD: 0.26, p=.351). In conclusion, we demonstrate the general effectiveness of a multipurpose exercise protocol on various risk factors and complaints related to the menopausal transition. Future assessments have to determine the exercise effects on BMD, possibly the most challenging physiologic outcome of this ongoing project.

High-velocity Resistance Training Improves Power Output Across The Entire 1RM Percentage Spectrum In Elderly Individuals

The aging process is related to impairments in several biological systems, such as the neuromuscular system. Of concern, considerable reductions in strength and power output are observed after the sixth decade of life, which are strongly related to declines in functional capacity. High-velocity resistance training (HVRT) is an alternative to counteract these impairments in the elderly population. PURPOSE: To compare the mean and peak power output adaptations to twelve weeks of HVRT. METHODS: Thirteen older adults (69.4 ± 6.2 years; 71.5 ± 16.0 kg; 161.8 ± 8.9 cm) were recruited and, after giving their informed consent, completed two familiarization sessions and, on a separate day (baseline), were assessed for their legpress one repetition maximum (1RM) and mean and peak power output at loads corresponding to 30-90% 1RM using a linear encoder. Four weeks after baseline and prior to the intervention (pre-intervention) both 1RM and power tests were repeated and all participants underwent twelve weeks of HVRT twice per week. The exercise training protocol was comprised of five exercises (legpress, knee extension, seated bench press, seated row and calf raise) and progressed from 1-3 sets of 10 repetitions per exercise at 40-60% 1RM. Tests were repeated post-intervention and mean and peak power comparisons were made using one-way ANOVAs with repeated measures and Bonferroni’s post hoc. RESULTS: Mean and peak power output results are shown in Figure 1. Peak power improved significantly at all loads when compared to both baseline and pre-intervention (all p < 0.05), while mean power output improved from 30-70% 1RM (all p < 0.05) but not at 80 and 90% 1RM. No differences were observed between baseline and pre-intervention measures (all p > 0.05). CONCLUSION: HVRT is an effective alternative to counteract power output declines across a wide range of loads in older adults. This is relevant as different functional tasks seem more associated to muscle power at different percentages of 1RM.

The Effect of High Volume Power Training on Repeated High-Intensity Performance and the Assessment of Repeat Power Ability: A Systematic Review.

High volume power training (HVPT) involves high volumes of high-velocity resistance training, with the aim to improve repeated high-intensity efforts (RHIEs). Repeat power ability (RPA) is the ability to repeatedly produce maximal or near maximal efforts. Assessments of RPA using external loading may determine the ability to perform repeat RHIEs typical of many sports and, therefore, provide useful information on the effectiveness of training. (1) Identify the different HVPT protocols; (2) examine the acute responses and chronic adaptations to different HVPT protocols; (3) identify different lower body RPA assessment protocols and highlight similarities, differences and potential limitations between each protocol, and; (4) describe the reliability and validity of RPA assessments. An electronic search was performed using SPORTDiscus, PubMed, CINAHL and Embase for studies utilising HVPT protocols and assessments of RPA. Eligible studies included peer-reviewed journal articles published in English. Twenty studies met the inclusion criteria of the final review. Of the eight longitudinal studies, three were rated as fair and five were rated as poor methodological quality, respectively. In contrast, all 12 cross-sectional studies were considered to have a low risk of bias. Preliminary evidence suggests that HVPT can enhance RHIE, RPA, anaerobic capacity, anaerobic power and aerobic performance. HVPT generally consists of 2-3 sessions per week, utilising loads of 30-40% 1 repetition maximum (RM), for 3-5 sets of 10-20 repetitions, with inter-set rest periods of 2-3min. RPA assessments can be valid and reliable and may provide useful information on an athlete's ability to perform RHIE and the success of HVPT programmes. HVPT can be used to improve a number of physical qualities including RPA and RHIE; while a variety of RPA assessments provide valid and reliable information regarding the athlete's ability to perform RHIEs. Considering the heterogeneity in the HVPT protocols currently used and the relatively low volume and quality of longitudinal publications in this area, further studies are needed to identify the effects of a variety of HVPT methods on RPA, RHIE and other performance outcomes and to identify the most valid and reliable RPA outcomes to use in such studies.

Effects of high-velocity resistance training and creatine supplementation in untrained healthy aging males.

The purpose was to investigate the effects of high-velocity resistance training (HVRT) and creatine supplementation in untrained healthy aging males. Participants were randomized to supplement with creatine (0.1 g·kg-1·day-1 of creatine + 0.1 g·kg-1·day-1 of maltodextrin) or placebo (0.2 g·kg-1·day-1 of maltodextrin) during 8 weeks of HVRT. Prior to and following HVRT and supplementation, assessments were made for muscle strength, muscle thickness, peak torque, and physical performance. There was a significant increase over time for all measures of muscle strength (p < 0.001), muscle thickness (p < 0.001), and some measures of peak torque (knee flexion; 1.05 and 3.14 rad/s; p < 0.001) and physical performance (balance board time-to-completion; p = 0.017). There was a group × time interaction for leg press strength (p = 0.044) and total lower-body strength (leg press, knee flexion, knee extension combined; p = 0.039). The creatine group experienced greater gains in leg press and total lower-body strength compared with the placebo group, with no other differences. HVRT increases muscle strength, muscle thickness, and some measures of peak torque and physical performance in untrained healthy aging males. The addition of creatine supplementation to HVRT further augments the gains in leg press and total lower-body strength. Novelty High-velocity resistance training increases muscle mass and performance. Creatine supplementation increases lower-body muscle strength. High-velocity resistance training and creatine supplementation are safe interventions for aging adults.

Correction: Effects of high-velocity resistance training and creatine supplementation in untrained healthy aging males.

The purpose was to investigate the effects of high-velocity resistance training (HVRT) and creatine supplementation in untrained healthy aging males. Participants were randomized to supplement with...

Effects of Low-Moderate Load High-Velocity Resistance Training on Physical Performance of Under-20 Futsal Players.

Resistance training (RT) is an effective methodology to improve physical performance of athletes. However, up to now, no studies have addressed the RT benefits in under-20 futsal players. The purpose of this study was to evaluate the effects of six weeks of RT with high-velocity movements, low-to-moderate loads, and low volume on physical performance of under-20 futsal players. A total of 21 players were divided into two groups: A control group (CG, n = 10) and a RT group (RTG, n = 11). The RTG performed two weekly training sessions constituted by leg-press, jumps, and sprints, along with three futsal training sessions, while the CG only performed the futsal training. Before and after the intervention, the sprint time in 0–10 m (T10), 10–20 m (T10–20), and 0–20 m (T20), the countermovement jump (CMJ) height, the T-Test time, the kicking ball speed (KBS), and the maximum dynamic strength in the leg-press, were assessed. In post-test, significant improvements in CMJ, T-Test, KBS, and leg-press were found for the RTG, whilst a significant decrease in T10–20 was evidenced in the CG. The present results suggested that RT based on high velocity movements, low-to-moderate loads, and low volume produce positive effects on physical performance of under-20 futsal players.

Effect of a 12-week mixed power training on physical function in dynapenic-obese older men: does severity of dynapenia matter?

Mobility disability affects nearly 15% of people aged 65 or over worldwide. Excess weight or obesity (OB), along with an accentuated loss of muscle strength (dynapenia), is recognized to be one of the most common risk factors for mobility impairment among the elderly. To investigate the effect of a 12-week mixed power training (MPT high-velocity resistance training mixed with functional exercises) on physical function in obese older men exhibiting different severities of dynapenia. Community-dwelling older men (69 ± 6 years) were assigned to the study if they were considered obese (OB, fat mass ≥ 25% body weight, BW) and to one of the two groups according to severity of dynapenia [(handgrip strength-HS)/BW]: type 1(OB-DY1) or type 2(OB-DY2), < 1 or 2SD from a young reference group. Participants followed a 12-week MPT, three times/week, 75min/session. Main outcomes included the performance on the 4-m and 6-min walking tests, Timed Up and Go, stair and balance tests. At baseline, OB-DY1 performed better than OB-DY2 in all functional tests (p < 0.05). Following the intervention, medium-to-large training effect size (ES) were observed for fat (ES = 0.21) and lean (ES = 0.32, p < 0.001) masses, functional performance (ES 0.11-0.54, p < 0.05), HS (ES = 0.10, p < 0.05) and lower limb muscle strength (ES = 0.67, p < 0.001) and power (ES = 0.60, p < 0.05). Training-by-group interaction showed that OB-DY1 lost more FM (ES = 0.11, p = 0.03) and OB-DY2 improved more HS (ES = 0.19, p = 0.006) than their counterparts. Seniors with obesity and severe dynapenia have poorer physical function than those in the early stage of dynapenia. Both seem to benefit from a high-velocity resistance training mixed with functional exercises, although by slightly different pathways.

Comparison of the acute effects of traditional versus high velocity resistance training on metabolic, cardiovascular, and psychophysiological responses in elderly hypertensive women.

ObjectivesThe aim of the present study was to compare the acute effects of traditional resistance training (RT) versus high velocity RT (HVRT) on metabolic, cardiovascular, and psychophysiological responses in elderly hypertensive women.MethodsFifteen elderly women (mean age ± standard deviation, 67.1±6.9 years) classified as having hypertension stage 1 or 2 were randomly allocated to complete traditional RT or HVRT; 1 week later, subjects allocated to RT completed the HVRT session and vice-versa. Heart rate, blood pressure, affective response, perceived effort, and blood samples analyzing lactate, nitrate, nitrite, oxidative damage (thiobarbituric acid reactive substances [TBARS]), and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid equivalent antioxidant capacity (TEAC) collected before and after training sessions were assessed. Nutritional counseling was provided regarding nutrients that could affect cardiovascular and nitrate/nitrite analysis.ResultsSystolic blood pressure was not statistically different (p>0.05) between conditions at the beginning and during 30 minutes after sessions. Diastolic blood pressure, rate pressure product, and heart rate were not statistically different (p>0.05) between conditions at the beginning and during 45 minutes after sessions. Nitric oxide was significantly higher (p<0.0005) for HVRT compared to RT after 30 minutes of exercise. TBARS and TEAC were significantly higher (p<0.05) for HVRT compared with RT only immediately after exercise. There were no differences for psychophysiological variables between protocols.ConclusionThe acute cardiovascular and metabolic responses, including oxidative stress, are transient and within normal values. Taken together with the positive affective responses, both HVRT and RT with this intensity and volume seem to be safe for elderly hypertensive women under medication.

Longitudinal comparison of low- and high-velocity resistance training in relation to body composition and functional fitness of older adults.

Functional mobility disability affects more than one in five adults over 70years and increases to 80% by 90years. While negative changes in mobility are multifactorial, deleterious body composition changes contribute significantly. Resistance training alters the negative trajectory of physical function as well as increases lean mass among older adults. Recently, high-velocity (HV) resistance training has been indicated as an effective intervention to increase lean mass and functional performance. The present investigation compared body composition, physical function, and muscular strength changes between HV and LV resistance training programs. Participants > 65years (n = 53) were randomly assigned to LV, HV, or active control (AC) group and participated in their respective intervention for 48weeks. Analysis of covariance revealed no significant body composition changes over time between groups (p > 0.05). Eight-foot up-and-go performance improved in the HV and AC groups (p < 0.05) with no change in the LV group (p > 0.05) over time. Muscular strength increased in both the LV and HV groups within the first 24weeks, while only in the LV group, muscular strength continued to increase from 24 to 48weeks (p < 0.05). Resistance training appears to be an effective intervention for improving aspects of physical function and muscular strength; however, no significant changes in body composition were observed over the 48-week intervention. Findings from the current investigation support use of resistance training for improving physical function among community-dwelling older adults.

Improved parent-reported mobility and achievement of individual goals on activity and participation level after functional power-training in young children with cerebral palsy: a double-baseline controlled trial.

In children with cerebral palsy (CP), strength training programs to improve walking capacity and participation in activities of daily living are commonly used in clinical practice, despite lacking evidence of its effectiveness. It has been suggested that strength training with high movement velocity could be more effective than traditional resistance training to improve functional abilities such as walking. In a recently published study, we have demonstrated the positive effects of functional high-velocity resistance (power) training on muscle strength and walking capacity in young children with CP. Whether this type of training is also effective in achieving individual predefined goals in daily activities and self-reported mobility limitations, has not yet been described however. To evaluate the effect of functional power-training on parent-reported mobility and achievement of individual goals on activity and participation level in young children with CP. A double-baseline design was used to compare a 14-week period usual care with a 14-week period of functional power-training (3 times a week) and a follow-up period of 14 weeks. A rehabilitation center, two special needs schools for children with physical disabilities, and a university medical center outpatient clinic. Twenty-two children with spastic CP (13 bilateral, GMFCS level I [N.=10] and level II [N.=12], mean age 7.5 years [SD 1.8, range 4-10 years]) and their parents participated. Outcome measures were goal attainment scaling (GAS) of individual daily activity related treatment goals, mobility performance as measured using the Functional Mobility Scale (FMS-5 m, 50 m and 500 m), and the parent-reported Mobility Questionnaire (MobQues). After power-training, 86% of children achieved or exceeded their goal, compared with 14% in the usual care period (P<.001). The probability of improvement by one point or more on the FMS-500 meter after functional power-training was 10 times higher, compared with the usual care period (Relative Risk=10.0 with 95% CI 1.4 - 71.3). No changes were found in the FMS-5m and FMS-50m categories. Improvement on the MobQues was significantly greater after power-training compared with usual care (7.9% (95% CI 2.7 - 13.0, P=.005)). The improvement in performance in the activities defined in the treatment goals continued during the follow-up period. The results indicated that functional power-training is an effective training to achieve personalized treatment goals for activities in daily life and parent-reported mobility performance in young children with cerebral palsy.

Improved Walking Capacity and Muscle Strength After Functional Power-Training in Young Children With Cerebral Palsy

Background. Strength training programs for children with cerebral palsy (CP) showed inconclusive evidence for improving walking, despite improvements in strength. Recent studies have suggested that strength training with high movement velocity is more effective for improving walking than traditional resistance training. Objective. The purpose of this study was to evaluate the effect of functional high-velocity resistance training (power-training) to improve muscle strength and walking capacity of children with CP. Method. Twenty-two children with spastic CP participated (13 bilateral, Gross Motor Function Classification System [GMFCS] level I [n = 10] and II [n = 12], 7.5 years [SD 1.8, range 4-10 years]). Within-subjects changes in a 14-weeks usual care period were compared with changes in a 14-week functional power-training period (in groups, 3×/wk). Outcome measures were the muscle power sprint test (MPST), 1-minute walk test (1MWT), 10-m shuttle run test (SRT), gross motor function (GMFM-66), isometric strength of lower-limb muscles and dynamic ankle plantar flexor strength. Results. Changes during the training period were significantly larger than changes in the usual care period for all outcome measures (P < .05). Large improvements were found during the training period for walking capacity (ΔMPST [mean]: 27.6 W [95%CI 15.84-39.46, 83% increase], Δ1MWT: 9.4 m [95% CI 4.17-14.68, 13%], ΔSRT: 4.2 [95%CI 2.57-5.83, 56%], ΔGMFM-66: 5.5 [95% CI 3.33-7.74, 7%]) and muscle strength (18%-128%), while outcomes remained stable in the usual care period. Conclusions. The results indicate that functional power-training is an effective training for improving walking capacity in young children with cerebral palsy.

Effect of High and Low Velocity Resistance Training on Speed Parameter of College Male Students

Effect of High and Low Velocity Resistance Training on Speed Parameter of College Male Students

Resistance training performed at distinct angular velocities elicits velocity-specific alterations in muscle strength and mobility status in older adults

BackgroundThe purpose of this study was to compare the effects of high and low velocity knee extension training on changes in muscle strength and mobility status in high-functioning older adults. MethodsTwenty-six (16 female, 10 male) older adults (mean age of 65) were randomized to either 6weeks of low velocity resistance training (LVRT) performed at 75°/s or high velocity resistance training (HVRT) performed at 240°/s. Both groups performed 3 sets of knee extension exercises at maximal effort, 3 times a week. Muscle strength was assessed through a range of testing velocities on an isokinetic dynamometer. Mobility status was assessed with the short physical performance battery (SPPB) and myosin heavy chain (MyHC) transcript levels were quantified via qRT-PCR. ResultsFrom baseline to post-training, there were several significant (P<0.05) differences in muscle strength and functional characteristics in LVRT (n=13) and HVRT (n=13) groups. From baseline to post-training, MyHC-α mRNA and MyHC-IIa mRNA showed a significant (P<0.05) increase within HVRT but MyHC-IIx mRNA did not change significantly. Our results demonstrate HVRT provides a greater number of muscular enhancements when compared to LVRT, particularly under conditions of high velocity muscle contraction. ConclusionHVRT is emerging as the optimal training stimulus for the older adult. The present study demonstrates, in addition to increased strength and functional outcomes, HVRT elicits a potentially therapeutic (i.e., slow to fast) transcriptional response in MyHC.

Changes in Lean Mass and Serum Myostatin with Habitual Protein Intake and High-Velocity Resistance Training.

Examine the associations between dietary protein intake, lean mass (LM), and serum myostatin (Mstn) levels among community-dwelling older adults participating in a 20-week high-velocity resistance training (HVRT) program. This longitudinal study consisted of 33 community-dwelling, older adults (mean age 77.0 years, SD = 6.4); all of which obtained physician clearance prior to study participation. Twenty-five females and eight males were randomized to a control (CON) or HVRT group. Anthropometric measures were obtained via dual energy x-ray absorptiometry (DXA) and peripheral venous blood draw used for serum myostatin analysis. Exercise was performed twice per week for 20 consecutive weeks. Food intake estimation with a diet history questionnaire (DHQ) was used for protein intake comparison to the recommended dietary allowance (RDA). All measures were recorded both prior to and following study participation. Altogether, protein was consumed in amounts more generous (1.01 ± 0.47 g·kg-1·d-1) than that of the RDA (0.8 g·kg-1·d-1). As a result of significant LM differences among men and women (p < 0.01), additional data were analyzed specific to sex. Serum myostatin was greater among females (6681.8 ± 3155.0 pg·mL-1) than males (5560.0 ± 2946.1 pg·mL-1); however, these values were not significantly different (p = 0.39). Combined, protein consumption and serum myostatin did not significantly influence LM among males (p = 0.09) or females (p = 0.71). Irrespective of training group, significant changes were not exhibited in dietary intake patterns, LM, or serum myostatin. Contrary to the proposed hypothesis, results suggest protein consumption and circulating serum myostatin levels did not significantly influence LM among older adults. Although HVRT positively impacts LM, neither exercise group displayed significant changes in LM. Therefore, further research is needed examining dietary intake, exercise modality, and myostatin downregulation as non-pharmacological approaches to combating sarcopenia.