Once-weekly resistance exercise improves muscle strength and neuromuscular performance in older adults

How many times per week should a muscle be trained to maximize muscle hypertrophy? A systematic review and meta-analysis of studies examining the effects of resistance training frequency

Training frequency is considered an important variable in the hypertrophic response to regimented resistance exercise. The purpose of this paper was to conduct a systematic review and meta-analysis of experimental studies designed to investigate the effects of weekly training frequency on hypertrophic adaptations. Following a systematic search of PubMed/MEDLINE, Scoups, and SPORTDiscus databases, a total of 25 studies were deemed to meet inclusion criteria. Results showed no significant difference between higher and lower frequency on a volume-equated basis. Moreover, no significant differences were seen between frequencies of training across all categories when taking into account direct measures of growth, in those considered resistance-trained, and when segmenting into training for the upper body and lower body. Meta-regression analysis of non-volume-equated studies showed a significant effect favoring higher frequencies, although the overall difference in magnitude of effect between frequencies of 1 and 3+ days per week was modest. In conclusion, there is strong evidence that resistance training frequency does not significantly or meaningfully impact muscle hypertrophy when volume is equated. Thus, for a given training volume, individuals can choose a weekly frequency per muscle groups based on personal preference.

Effect of Resistance Training Frequency on Gains in Muscular Strength: A Systematic Review and Meta-Analysis

BACKGROUND

Current recommendations on resistance training (RT) frequency for gains in muscular strength are based on extrapolations from limited evidence on the topic, and thus their practical applicability remains questionable.

OBJECTIVE

To elucidate this issue, we conducted a systematic review and meta-analysis of the studies that compared muscular strength outcomes with different RT frequencies.

METHODS

To carry out this review, English-language literature searches of the PubMed/MEDLINE, Scopus, and SPORTDiscus databases were conducted. The meta-analysis was performed using a random-effects model. The meta-analysis models were generated with RT frequencies classified as a categorical variable as either 1, 2, 3, or 4+ times/week, or, if there were insufficient data in subgroup analyses, the training frequencies were categorized as 1, 2, or 3 times/week. Subgroup analyses were performed for potential moderators, including (1) training volume; (2) exercise selection for the 1 repetition maximum (RM) test (for both multi-joint and single-joint exercises); (3) upper and lower body strength gains; (4) training to muscular failure (for studies involving and not involving training to muscular failure); (5) age (for both middle-aged/older adults and young adults); and (6) sex (for men and for women). The methodological quality of studies was appraised using the modified Downs and Black checklist.

RESULTS

A total of 22 studies were found to meet the inclusion criteria. The average score on the Downs and Black checklist was 18 (range 13-22 points). Four studies were classified as being of good methodological quality, while the rest were classified as being of moderate methodological quality. Results of the meta-analysis showed a significant effect (p = 0.003) of RT frequency on muscular strength gains. Effect sizes increased in magnitude from 0.74, 0.82, 0.93, and 1.08 for training 1, 2, 3, and 4+ times per week, respectively. A subgroup analysis of volume-equated studies showed no significant effect (p = 0.421) of RT frequency on muscular strength gains. The subgroup analysis for exercise selection for the 1RM test suggested a significant effect of RT frequency on multi-joint (p < 0.001), but not single-joint, 1RM test results (p = 0.324). The subgroup analysis for upper and lower body showed a significant effect of frequency (p = 0.004) for upper body, but not lower body, strength gains (p = 0.070). In the subgroup analysis for studies in which the training was and was not carried out to muscular failure, no significant effect of RT frequency was found. The subgroup analysis for the age groups suggested a significant effect of training frequency among young adults (p = 0.024), but not among middle-aged and older adults (p = 0.093). Finally, the subgroup analysis for sex indicated a significant effect of RT frequency on strength gains in women (p = 0.030), but not men (p = 0.190).

CONCLUSIONS

The results of the present systematic review and meta-analysis suggest a significant effect of RT frequency as higher training frequencies are translated into greater muscular strength gains. However, these effects seem to be primarily driven by training volume because when the volume is equated, there was no significant effect of RT frequency on muscular strength gains. Thus, from a practical standpoint, greater training frequencies can be used for additional RT volume, which is then likely to result in greater muscular strength gains. However, it remains unclear whether RT frequency on its own has significant effects on strength gain. It seems that higher RT frequencies result in greater gains in muscular strength on multi-joint exercises in the upper body and in women, and, finally, in contrast to older adults, young individuals seem to respond more positively to greater RT frequencies. More evidence among resistance-trained individuals is needed as most of the current studies were performed in untrained participants.

Physical activity for brain health in older adults

Physical activity is a promising strategy for dementia prevention and disease modification. Here, we provide a narrative review of the current evidence from epidemiological and intervention studies on the role of physical activity and exercise in promoting cognitive health in older adults both without and with cognitive impairment. We highlight some of the potential underlying mechanisms and discuss biological sex as a potential moderating factor. We conclude with limitations and future directions for this rapidly expanding line of research.

Age-related changes in skeletal muscle: changes to life-style as a therapy

As we age, there is an age-related loss in skeletal muscle mass and strength, known as sarcopenia. Sarcopenia results in a decrease in mobility and independence, as well as an increase in the risk of other morbidities and mortality. Sarcopenia is therefore a major socio-economical problem. The mechanisms behind sarcopenia are unclear and it is likely that it is a multifactorial condition with changes in numerous important mechanisms all contributing to the structural and functional deterioration. Here, we review the major proposed changes which occur in skeletal muscle during ageing and highlight evidence for changes in physical activity and nutrition as therapeutic approaches to combat age-related skeletal muscle wasting.

Resistance training frequency and skeletal muscle hypertrophy: A review of available evidence

OBJECTIVES

Current reviews and position stands on resistance training (RT) frequency and associated muscular hypertrophy are based on limited evidence holding implications for practical application and program design. Considering that several recent studies have shed new light on this topic, the present paper aimed to collate the available evidence on RT frequency and the associated effect on muscular hypertrophy.

DESIGN

Review article.

METHODS

Articles for this review were obtained through searches of PubMed/MEDLINE, Scopus, and SPORTDiscus. Both volume-equated (studies in which RT frequency is the only manipulated variable) and non-volume-equated (studies in which both RT frequency and volume are the manipulated variables) study designs were considered.

RESULTS

Ten studies were found that used direct site-specific measures of hypertrophy, and, in general, reported that RT once per week elicits similar hypertrophy compared to training two or three times per week. In addition, 21 studies compared different RT frequencies and used lean body mass devices to estimate muscular growth; most of which reported no significant differences between training frequencies. Five studies were identified that used circumference for estimating muscular growth. These studies provided findings that are difficult to interpret, considering that circumference is a crude measure of hypertrophy (i.e., it does not allow for the differentiation between adipose tissue, intracellular fluids, and muscle mass).

CONCLUSIONS

Based on the results of this review, it appears that under volume-equated conditions, RT frequency does not seem to have a pronounced effect of gains in muscle mass.

Sarcopenic obesity in older adults: aetiology, epidemiology and treatment strategies

The prevalence of obesity in combination with sarcopenia (the age-related loss of muscle mass and strength or physical function) is increasing in adults aged 65 years and older. A major subset of adults over the age of 65 is now classified as having sarcopenic obesity, a high-risk geriatric syndrome predominantly observed in an ageing population that is at risk of synergistic complications from both sarcopenia and obesity. This Review discusses pathways and mechanisms leading to muscle impairment in older adults with obesity. We explore sex-specific hormonal changes, inflammatory pathways and myocellular mechanisms leading to the development of sarcopenic obesity. We discuss the evolution, controversies and challenges in defining sarcopenic obesity and present current body composition modalities used to assess this condition. Epidemiological surveys form the basis of defining its prevalence and consequences beyond comorbidity and mortality. Current treatment strategies, and the evidence supporting them, are outlined, with a focus on calorie restriction, protein supplementation and aerobic and resistance exercises. We also describe weight loss-induced complications in patients with sarcopenic obesity that are relevant to clinical management. Finally, we review novel and potential future therapies including testosterone, selective androgen receptor modulators, myostatin inhibitors, ghrelin analogues, vitamin K and mesenchymal stem cell therapy.

Weekly Training Frequency Effects on Strength Gain: A Meta-Analysis

Background

The current recommendations for resistance training (RT) frequency range from 2 to 5 days per week (days week^− 1) depending on the subjects’ training status. However, the relationship between RT frequency and muscular strength remains controversial with reported variances existing across different population groups. We conducted a meta-analysis that (1) quantified the effects of low (LF; 1 day week^− 1), medium (MF; 2 days week^− 1), or high (HF; ≥ 3 days week^− 1) RT frequency on muscular strength per exercise; (2) examined the effects of different RT frequency on one repetition maximum (1RM) strength gain profiles (multi-joint exercises and single joint exercises); (3) examined the effects of different RT frequency on 1RM strength gain when RT volume is equated; and (4) examined the effects of different RT frequency on 1RM strength gains on upper and lower body.

Methods

Computerised searches were performed using the terms ‘strength training frequency’, ‘resistance training frequency’, ‘training frequency’, and ‘weekly training frequency’. After review, 12 studies were deemed suitable according to pre-set eligibility criteria. Primary data were pooled using a random-effects model. Outcomes analysed for main effects were pre- to post strength change with volume-equated studies that combined multi-joint and isolation exercise; isolation-only exercise and untrained subjects only. Heterogeneity between studies was assessed using I² and Cochran’s Q statistics with funnel plots used to assess publication bias and sensitivity analyses calculated for subgroups.

Results

Pre- versus post-training strength analysis comprised of 74 treatment groups from 12 studies. For combined multi-joint and isolation exercises, there was a trend towards higher RT frequency compared with lower frequency [mean effect size (ES) 0.09 (95% CI − 0.06–0.24)] however not significant (p = 0.25). Volume-equated pre- to post-intervention strength gain was similar when LF was compared to HF [mean ES 0.03 (95% CI − 0.20–0.27); p = 0.78]. Upper body pre- to post-intervention strength gain was greater when HF was compared with LF [mean ES 0.48 (95% CI 0.20–0.76)] with significant differences between frequencies (p < 0.01). Upper body pre- to post-intervention strength gain was similar when MF was compared with LF (ES 0.12; 95% CI − 0.22–0.47); p = 0.48]. There was no significant difference in lower body mean ES between HF and LF [mean ES 0.21(95% CI − 0.55–0.13); p = 0.22]. There was a trend towards a difference in mean ES between MF and HF [mean ES 0.41(95% CI − 0.26–1.09); however, the effect was not significant (p = 0.23).

Conclusions

The existing data does not provide a strong correlation between increased weekly training frequency (HF) and maximal strength gain in upper and lower body resistance exercises for a mixed population group. When RT is volume-equated for combined multi-joint and isolation exercises, there is no significant effect of RT frequency on muscular strength gain. More investigations are required to explore the effects of varying weekly training frequencies adequately.

Motivational characteristics and resistance training in older adults: A randomized controlled trial and 1-year follow-up

The aim of this study was to investigate the effects of a 9-month supervised resistance training intervention on motivational and volitional characteristics related to exercise, and whether the absolute level and/or intervention-induced change in these characteristics predict self-directed continuation of resistance training 1 year after the intervention. Community dwelling older adults aged 65-75, who did not fulfill physical activity recommendations, were randomized into resistance training intervention groups: training once- (n = 26), twice- (n = 27), three-times-a-week (n = 28) or non-training control group (n = 25). Training groups participated in supervised resistance training for 9 months: during months 1-3 all groups trained twice-a-week and then with allocated frequencies during months 4-9. Exercise-related motivation, self-efficacy, and planning were measured with questionnaires at baseline, month-3 and month-9. The continuance of resistance training was determined by interviews 6 and 12 months after the end of the intervention. The intervention improved action and coping planning as well as intrinsic motivation (group × time P < .05). During 1-year follow-up, 54% of participants did not continue self-directed regular resistance training, 22% continued regular resistance training once-a-week, and 24% twice-a-week. Increases in exercise self-efficacy and intrinsic motivation related to training during the intervention predicted continuation of resistance training twice-a-week. Resistance training improved exercise-related motivational and volitional characteristics in older adults. These improvements were linked to continuing resistance training 1 year after the supervised intervention. The role of these characteristics should be taken into account when promoting long-term resistance training participation among older adults.

Feasibility and Preliminary Efficacy of a 10-Week Resistance and Aerobic Exercise Intervention During Neoadjuvant Chemoradiation Treatment in Rectal Cancer Patients

Background: Neoadjuvant chemoradiation treatment (CRT) in rectal cancer patients is associated with a reduction in physical capacity, lean mass and increased fatigue. As a countermeasure to these treatment-related adverse effects, we examined the feasibility and preliminary efficacy of a 10-week exercise program during CRT. Methods: Ten rectal cancer patients (7 men, aged 27-70 years, body mass index = 26.4 ± 3.8 kg/m²) receiving CRT undertook supervised resistance and aerobic exercise twice weekly. Assessments were undertaken pre- and post-intervention for upper and lower body muscle strength by 1-RM, muscle endurance, physical performance tests, body composition by dual X-ray absorptiometry, quality of life, and fatigue. Results: There was a significant loss in appendicular skeletal muscle (−1.1 kg, P = .012), and fat mass (−0.8 kg, P = .029) following CRT. Despite the loss in skeletal muscle, leg press (P = .030) and leg extension (P = .046) strength improved by 27.2% and 22.7%, respectively, and leg press endurance by 76.7% (P = .007). Changes in strength were accompanied by improved performance (P < .05) in 6-m fast walking speed (6.9%) and dynamic balance as determined by the 6-m backwards walk (15.5%). There was minimal change in quality of life and fatigue, and no adverse events related to training. Conclusions: Exercise during neoadjuvant CRT appears to be feasible and well tolerated in rectal cancer patients and may enhance physical function while minimizing adverse changes in body composition and cancer-related fatigue. These initial findings need to be confirmed in randomized controlled trials.

Exercise Improves V˙O2max and Body Composition in Androgen Deprivation Therapy-treated Prostate Cancer Patients

INTRODUCTION

Prostate cancer is the most common cancer in men, and patients treated with androgen deprivation therapy (ADT) experience unfavorable changes in body composition and associated metabolic complications, which can increase the risk of cardiovascular disease. We examined the effect of a 6-month program of aerobic and resistance exercise aimed at improving body composition and cardiorespiratory health in this population.

METHODS

Ninety-seven men (43-90 yr) with localized prostate cancer receiving ADT were randomized to either exercise (EX, n = 50) or usual care (CON, n = 47). Supervised exercise was undertaken twice weekly at moderate to high intensity. Measures of cardiorespiratory capacity (V˙O2max), resting metabolic rate, central blood pressure, hemodynamic variables, blood markers, and body composition were assessed.

RESULTS

There was a significant group-time interaction present for V˙O2max (P = 0.033) with a treatment effect for EX of 0.11 L·min (95% confidence interval [CI] = 0.04-0.19) (relative to body mass = 1.3 mL·kg·min, 95% CI = 0.3-2.3) and fat oxidation (P = 0.037) of 12.0 mg·min (95% CI = 2.3-21.7). Similarly, there was a significant improvement in glucose (P < 0.001) for EX of -0.5 mmol·L (95% CI = -0.8 to -0.3), with no change in prostate-specific antigen or testosterone as a result of exercise. Body composition was enhanced for EX with adjusted mean differences in lean mass (P = 0.015) of 0.8 kg (95% CI = 0.3-1.3), total fat mass (P = 0.020) of -1.1 kg (95% CI = -1.8 to -0.5), and trunk fat mass (P < 0.001) of -1.0 kg (95% CI = -1.4 to -0.6).

CONCLUSION

A 6-month combined aerobic and resistance exercise program has a significant favorable effect on cardiorespiratory capacity, resting fat oxidation, glucose, and body composition despite the adverse effects of hormone suppression. Combined aerobic and resistance training should be considered a key adjuvant component in men undergoing ADT for the treatment of prostate cancer.

Why intensity is not a bad word: Optimizing health status at any age

Age-related declines in health and function make locomotion increasingly difficult leading to reductions in non-exercise activity thermogenesis (NEAT), skeletal muscle size and strength, and increased adiposity. Exercise is an important strategy to attenuate loss of function through the life cycle. Despite claims to the contrary, high-intensity exercise is important for the prevention of obesity and sarcopenia with advancing age. Therefore, the purpose of this mini-review is to present literature supporting the contention that low volume, high-intensity aerobic and/or resistance training can slow sarcopenia, sustain ease of movement, stimulate NEAT, and attenuate the accretion of fat mass.

Frailty in elderly diabetes patients

Frailty is a state of vulnerability and a consequence of cumulative decline in multiple physiological systems over a lifespan. The occurrence of frailty depends on deterioration in muscle and nerve function, declining cardiopulmonary reserve and loss of executive function. Diabetes mellitus (DM) often causes functional impairment in each of the above systems, thus leading to a loss of whole body homeostasis and deterioration in physical function. Inability of self-management in DM patients may also have considerable impact on the development of sarcopenia/frailty. Thus, there may be positive feedback between the progression of diabetic complications and frailty/sarcopenia. While various factors are involved in this process, insulin resistance or insulin depletion may be an important factor in the progression of frailty in diabetes patients since insulin is well known to be an anabolic hormone in muscle. Interestingly, in our study targeting elderly DM patients, low HbA1c was a significant and independent risk factor for frailty, as assessed using a broad sense frailty scale, the Clinical Frailty Scale (CSF), suggesting that reverse metabolism due to malnutrition in elderly type 2 DM patients might be involved. Therefore, an intervention that includes proper nutrition and exercise training may be essential for the prevention of frailty. The pathogenesis of frailty in DM patients is extensively discussed in this review.

Proposing Development and Utility of a Mobility Composite Measure in Patients with a Neurologic Disorder

Background

Outcome measures typically assess single domains making holistic assessment difficult. Our purpose was to develop a mobility composite measure (MCM) based on four commonly used outcome measures and compare this composite score to the individual measures in patients with neurologic disorders.

Methods

We retrospectively reviewed 148 medical records for inclusion of primary neurologic diagnosis and scoring for 5 times sit-to-stand test (5TSST), 10-meter walk test (10MWT), 2-minute walk test (2MWT), and activities-specific balance confidence (ABC) scale.

Results

After establishing that a single concept was being assessed with interitem correlations, raw scores were converted to percentage of normal and combined into the MCM for analysis from admission to discharge. Scores on each measure significantly improved after intervention (5TSST, p < .001; 10MWT, p < .001; 2MWT, p < .001; ABC, p = .02). Mean MCM (n = 93) admission scores were 67.55 ± 31.88% and discharge scores were 74.81 ± 34.39% (p = .002). On average, patients improved 7.26% on the MCM exceeding the threshold of expected error (MDC₉₅ = 3.59%).

Conclusions

MCM detected change in patient outcomes statistically and clinically and appears to capture a holistic picture of functional status. We recommend a prospective study to further investigate a "composite measure" incorporating measures from several functional domains.

Feasibility of Presurgical Exercise in Men With Prostate Cancer Undergoing Prostatectomy

BACKGROUND

Prostatectomy is associated with short- and long-term morbidity, which includes attenuation of muscle function and deterioration of lean body mass. Physical function is a known predictor of morbidity and mortality, with initial evidence indicating that presurgical exercise is associated with fewer postsurgical complications and shorter hospitalization. The aim was to determine the feasibility of a supervised presurgical exercise program for prostate cancer (PCa) patients scheduled for prostatectomy.

METHODS

Ten men (68+6.4 years old) with localized PCa undertook a 6-week resistance and aerobic exercise program prior surgery. Training was undertaken twice weekly and patients were assessed at baseline, presurgery, and 6 weeks postsurgery. Outcome measures included muscle and physical performance, body composition, urinary incontinence and questionnaire.

RESULTS

Muscle strength increased by 7.5% to 24.3% ( P < .05) from baseline to presurgery but decreased to pretraining levels postsurgery, except for knee extensor strength ( P = .247). There were significant improvements ( P < .05) in the 6-m fast walk (9.3%), 400-m walk (7.4%), and chair rise (12.3%) at presurgery. Following surgery, improvements in physical performance were maintained. There was no change in lean or fat mass prior to surgery, but lean mass declined by 2.7 kg ( P = .014) following surgery. There were no adverse effects from the exercise program.

CONCLUSIONS

Exercise undertaken prior to prostatectomy improved muscle and physical performance, with functional benefits maintained 6 weeks postsurgery. Presurgical exercise for PCa patients has the potential to facilitate recovery by improving physical reserve capacity, especially in men with poor muscle nd physical performance.

Do isometric, isotonic and/or isokinetic strength trainings produce different strength outcomes?

INTRODUCTION

Several studies have been developed to determine which type of muscular action (isometric, isotonic and isokinetic) elicits more gains in functional strength and muscle mass. The comparisons between training outcomes are inconclusive due to lack of exercise standardization.

OBJECTIVE

To compare muscle strength, mass, and functional performance in response to isometric, isotonic, and isokinetic contractions, when training loads (volume and intensity) are equated.

METHOD

Data were derived from a university community-recruited sample (n = 31 men).

INTERVENTIONS

Untrained men were assigned to isotonic (IT), isometric (IM), or isokinetic (IK) group, and trained their dominant quadriceps muscle 3 sessions/week for 8 weeks with a dynamometer. Muscle strength was assessed using Cybex 6000 dynamometer; the triple-hop-distance test was used to assess functional performance, and dual energy x-ray absorptiometry to assess lean muscle mass.

RESULTS

After training, muscle lean muscle mass increased in isometric (+3.1%, p < 0.01) and isotonic groups (+3.9%, p < 0.01); only the isokinetic group showed a significant improvement in the triple-hop-distance test (4.84%, p < 0.01).

CONCLUSION

Clinicians should consider isometric training as an alternative for isotonic training to gain muscle mass, and isokinetic training to improve functional performance of daily activities and/or sports.

Effects of different strength training frequencies on maximum strength, body composition and functional capacity in healthy older individuals

There is controversy in the literature regarding the dose-response relationship of strength training in healthy older participants. The present study determined training frequency effects on maximum strength, muscle mass and functional capacity over 6months following an initial 3-month preparatory strength training period. One-hundred and six 64-75year old volunteers were randomly assigned to one of four groups; performing strength training one (EX1), two (EX2), or three (EX3) times per week and a non-training control (CON) group. Whole-body strength training was performed using 2-5 sets and 4-12 repetitions per exercise and 7-9 exercises per session. Before and after the intervention, maximum dynamic leg press (1-RM) and isometric knee extensor and plantarflexor strength, body composition and quadriceps cross-sectional area, as well as functional capacity (maximum 7.5m forward and backward walking speed, timed-up-and-go test, loaded 10-stair climb test) were measured. All experimental groups increased leg press 1-RM more than CON (EX1: 3±8%, EX2: 6±6%, EX3: 10±8%, CON: -3±6%, P<0.05) and EX3 improved more than EX1 (P=0.007) at month 9. Compared to CON, EX3 improved in backward walk (P=0.047) and EX1 in timed-up-and-go (P=0.029) tests. No significant changes occurred in body composition. The present study found no evidence that higher training frequency would induce greater benefit to maximum walking speed (i.e. functional capacity) despite a clear dose-response in dynamic 1-RM strength, at least when predominantly using machine weight-training. It appears that beneficial functional capacity improvements can be achieved through low frequency training (i.e. 1-2 times per week) in previously untrained healthy older participants.

Lower Jump Power Rather Than Muscle Mass Itself is Associated with Vertebral Fracture in Community-Dwelling Elderly Korean Women

Sarcopenia is considered to be a risk factor for osteoporotic fracture, which is a major health problem in elderly women. In this study, we aimed to investigate the association of sarcopenia, with regard to muscle mass and function, with prevalent vertebral fracture in community-dwelling elderly women. We recruited 1281 women aged 64 to 87 years from the Korean Urban Rural Elderly cohort study. Muscle mass and function were measured using bioimpedance analysis and jumping mechanography. Skeletal muscle index (SMI) and jump power were used as an indicator of muscle mass and function, respectively. Among the participants, we observed 282 (18.9%) vertebral fractures and 564 (44.0%) osteoporosis. Although age, body mass index, and prevalence of osteoporosis increased as both SMI and jump power decreased, prevalence of vertebral fracture increased only when jump power decreased. In univariate analysis, compared with the highest quartile of jump power, the lowest quartile had a significant odds ratio of 2.80 (95% CI 1.79-4.36) for vertebral fracture. This association between jump power and vertebral fracture remained significant, with an odds ratio of 3.04 (95% CI 1.77-5.23), even after adjusting for other risk factors including age, bone mineral density, previous fracture, and cognitive function. In contrast, there was no association between SMI and vertebral fracture. Based on our results, low jump power, but not SMI, is associated with vertebral fracture in community-dwelling elderly Korean women. This finding suggests that jump power may have a more important role than muscle mass itself for osteoporotic fracture.

Effects of resistance training frequency on cardiorespiratory fitness in older men and women during intervention and follow-up

This study investigated the effects of resistance training (RT) performed with different frequencies, including a follow-up period, on cardiorespiratory fitness in healthy older individuals. Eighty-eight men and women (69±3years, 167±9cm and 78±14kg) were randomly placed into four groups: training one- (M1=11, W1=12), two- (M2=7, W2=14), or three- (M3=11, W3=13) times-per-week or a non-training control group (MCon=11, WCon=9). During months 1-3, all subjects trained two-times-per-week while during the subsequent 6months, training frequency was set according to the group. Oxygen consumption (cycling economy: CE), gross efficiency (GE), blood lactate concentrations (La) and heart rate (HR) were evaluated during a submaximal cycle ergometer test. Hemoglobin (Hb), hematocrit (Hct), heart rate (HRrest) and body composition by DXA were also measured at rest. Maximal strength was measured by a 1-RM leg press test. Most improvements in CE, GE, La and HR occurred in all groups during months 1-3. No additional statistically significant improvements were observed during months 4-9, although effect sizes for the change in CE and GE at higher workloads indicated a dose-response pattern in men (CE at 75W: M1 g=0.13, M2 g=-0.58, M3 g=-0.89; 100W: M1 g=0.43, M2 g=-0.59, M3 g=-0.68) i.e. higher training frequency (two- and three-times-per-week versus one-time-per-week) led to greater improvements once the typical plateau in performance had occurred. Hb increased in W1 and W2, while no changes were observed in Hct or HRrest. 1-RM increased from months 1-3 in all intervention groups (except M2) and from month 4-9 only in M3 and in all women intervention groups. During follow-up, maximal strength was maintained but cycling economy returned to the baseline values in all training groups. These data indicate that RT led to significant improvements in cardiorespiratory fitness during the initial 3months of training. This was partly explained by the RT protocol performed but further improvements may require higher training frequency. These changes are likely to be originated by the improved cardiorespiratory functions rather than neuromuscular adaptations evidenced by a lack of significant relationship during the intervention as well as the divergent results during follow-up.

Effects of Different Exercise Modalities on Fatigue in Prostate Cancer Patients Undergoing Androgen Deprivation Therapy: A Year-long Randomised Controlled Trial

BACKGROUND

Physical exercise mitigates fatigue during androgen deprivation therapy (ADT); however, the effects of different exercise prescriptions are unknown.

OBJECTIVES

To determine the long-term effects of different exercise modes on fatigue in prostate cancer patients undergoing ADT.

DESIGN, SETTING, AND PARTICIPANTS

Between 2009 and 2012, 163 prostate cancer patients aged 43-90 y on ADT were randomised to exercise targeting the musculoskeletal system (impact loading+resistance training; ILRT; n=58), the cardiovascular and muscular systems (aerobic+resistance training; ART; n=54), or to usual care/delayed exercise (DEL; n=51) for 12 mo across university-affiliated exercise clinics in Australia.

INTERVENTION

Supervised ILRT for 12 mo, supervised ART for 6 mo followed by a 6-mo home program, and DEL received a printed booklet on exercise information for 6 mo followed by 6-mo stationary cycling exercise.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Fatigue was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 36 and vitality using the Short Form-36. Analysis of variance was used to compare outcomes for groups at 6 mo and 12 mo.

RESULTS AND LIMITATIONS

Fatigue was reduced (p=0.005) in ILRT at 6 mo and 12 mo (∼5 points), and in ART (p=0.005) and DEL (p=0.022) at 12 mo. Similarly, vitality increased for all groups (p≤0.001) at 12 mo (∼4 points). Those with the highest levels of fatigue and lowest vitality improved the most with exercise (p_trend<0.001). A limitation was inclusion of mostly well-functioning individuals.

CONCLUSIONS

Different exercise modes have comparable effects on reducing fatigue and enhancing vitality during ADT. Patients with the highest levels of fatigue and lowest vitality had the greatest benefits.

PATIENT SUMMARY

We compared the effects of different exercise modes on fatigue in men on androgen deprivation therapy. All exercise programs reduced fatigue and enhanced vitality. We conclude that undertaking some form of exercise will help reduce fatigue, especially in those who are the most fatigued.

How much will older adults exercise? A feasibility study of aerobic training combined with resistance training

Background

Both aerobic training (AT) and resistance training (RT) have multidimensional health benefits for older adults including increased life expectancy and decreased risk of chronic diseases. However, the volume (i.e., frequency*time) of AT combined with RT in which untrained older adults can feasibly and safely participate remains unclear. Thus, our primary objective was to investigate the feasibility and safety of a high-volume exercise program consisting of twice weekly AT combined with twice weekly RT (i.e., four times weekly exercise) on a group of untrained older adults. In addition, we investigated the effects of the program on physical function, aerobic capacity, muscular strength, and explored factors related to participant adherence.

Methods

We recruited eight inactive older adults (65+ years) to participate in a 6-week, single-group pre-post exercise intervention, consisting of 2 days/week of AT plus 2 days/week of progressive RT for 6 weeks. We recorded program attendance and monitored for adverse events during the course of the program. Participants were tested at both baseline and follow-up on the following: (1) physical function (i.e., timed-up-and-go test (TUG) and short physical performance battery (SPPB)), (2) aerobic capacity (VO₂max) using the modified Bruce protocol; and (3) muscular strength on the leg press and lat pull-down. Post intervention, we performed qualitative semi-structured interviews of all participants regarding their experiences in the exercise program. We used these responses to examine themes that may affect continued program adherence to a high-volume exercise program.

Results

We recorded an average attendance rate of 83.3% with the lowest attendance for one session being five out of eight participants; no significant adverse events occurred. Significant improvements were observed for SPPB score (1.6; 95% CI: [0.3, 2.9]), VO₂max (8.8 ml/kg/min; 95% CI: [2.8, 14.8]), and lat pull-down strength (11.8 lbs; 95% CI: [3.3, 20.2]). Qualitative results revealed two themes that promote older adults’ adherence: (1) convenience of the program and (2) the social benefits of exercise.

Conclusions

Our findings suggest untrained older adults can be successful at completing twice weekly AT combined with twice weekly progressive RT; however, these exercise programs should be group-based in order to maintain high adherence.

Nutrition therapy with high intensity interval training to improve prostate cancer-related fatigue in men on androgen deprivation therapy: a study protocol

Background

Cancer-related fatigue is one of the most prevalent, prolonged and distressing side effects of prostate cancer treatment with androgen deprivation therapy. Preliminary evidence suggests natural therapies such as nutrition therapy and structured exercise prescription can reduce symptoms of cancer-related fatigue. Men appear to change their habitual dietary patterns after prostate cancer diagnosis, yet prostate-specific dietary guidelines provide limited support for managing adverse side effects of treatment. The exercise literature has shown high intensity interval training can improve various aspects of health that are typically impaired with androgen deprivation therapy; however exercise at this intensity is yet to be conducted in men with prostate cancer. The purpose of this study is to examine the effects of nutrition therapy beyond the current healthy eating guidelines with high intensity interval training for managing cancer-related fatigue in men with prostate cancer treated with androgen deprivation therapy.

Methods/design

This is a two-arm randomized control trial of 116 men with prostate cancer and survivors treated with androgen deprivation therapy. Participants will be randomized to either the intervention group i.e. nutrition therapy and high intensity interval training, or usual care. The intervention group will receive 20 weeks of individualized nutrition therapy from an Accredited Practising Dietitian, and high intensity interval training (from weeks 12–20 of the intervention) from an Accredited Exercise Physiologist. The usual care group will maintain their standard treatment regimen over the 20 weeks. Both groups will undertake primary and secondary outcome testing at baseline, week 8, 12, and 20; testing includes questionnaires of fatigue and quality of life, objective measures of body composition, muscular strength, cardiorespiratory fitness, biomarkers for disease progression, as well as dietary analysis. The primary outcomes for this trial are measures of fatigue and quality of life.

Discussion

This study is the first of its kind to determine the efficacy of nutrition therapy above the healthy eating guidelines and high intensity interval training for alleviating prostate-cancer related fatigue. If successful, nutrition therapy and high intensity interval training may be proposed as an effective therapy for managing cancer-related fatigue and improving quality of life in men during and after prostate cancer treatment.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12615000512527. Trial registered on the 22/5/2015.

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

OBJECTIVES

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.

DESIGN, SETTING, AND PARTICIPANTS

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.

MEASUREMENTS

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.

RESULTS

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.

CONCLUSIONS

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.

Bone mineral density is increased after a 16-week resistance training intervention in elderly women with decreased muscle strength

OBJECTIVE

Non-pharmacological interventions are important in reducing risk for osteoporotic fractures. We investigated the effects of a 16-week individualized resistance training intervention on bone mineral density (BMD), bone turnover markers and 10-year relative risk (RR) for osteoporotic fracture.

DESIGN

Interventional study with a follow-up.

METHODS

In total, 37 elderly women (mean age 71.9 ± 3.1 years) with decreased muscle strength participated in the resistance training intervention three times per week with 60 min per session for 16 weeks under the supervision of a licensed physiotherapist. Total hip BMD with quantitative CT, bone markers (sclerostin, osteocalcin, CTX, PINP, IGF-1, 25(OH)-D) and 10-year RR for osteoporotic fracture were measured at baseline, post-intervention and at 1-year follow-up after the end of the intervention. Eleven age- and sex-matched controls did not participate in the intervention but were studied at baseline and at 1-year follow-up.

RESULTS

Resistance training seemed to increase total hip BMD by 6% (P = 0.005). Sclerostin (P < 0.001) and total osteocalcin (P = 0.04) increased while other bone markers remained unchanged. A 10-year RR for major osteoporotic and hip fracture remained unchanged. At follow-up total hip BMD (P < 0.001) decreased back to the baseline level with a simultaneous decrease in serum sclerostin (P = 0.045), CTX (P < 0.001) and an increase in 25(OH)-D (P < 0.001), 10-year RR for major osteoporotic (P = 0.002) and hip fracture (P = 0.01).

CONCLUSIONS

Our findings suggest an important role of continuous supervised resistance training for the prevention of osteoporotic fractures in elderly women with decreased muscle strength.

High Cardiorespiratory Fitness Is Associated with Reduced Risk of Low Bone Density in Postmenopausal Women

PURPOSE

The goal of this study was to determine the association between cardiorespiratory fitness (CRF) and bone mineral density (BMD) of the femoral neck (FN) in postmenopausal women using existing Cooper Center Longitudinal Study data.

MATERIALS AND METHODS

A cohort of 1,720 predominantly healthy Caucasian women (57.1 ± 6.9 years) underwent preventive medical examinations that included CRF assessment by maximal Balke treadmill testing and measurement of BMD by dual-energy X-ray absorptiometry. CRF was estimated from total treadmill time and categorized into five categories of CRF (further defined as fitness category 1 = low fitness, 2-3 = moderate fitness, and 4-5 = high fitness). Logistic regression was used to characterize the association between CRF and BMD, adjusting for age, weight, and resistance activity level.

RESULTS

Overall, the mean body-mass index (BMI) for all subjects was 25.0 ± 4.5 kg/m2, although BMI was in the obese range in the low fitness group. The prevalence of osteoporosis (T-score ≤ -2.5 at the FN) was greater in the low fit group than moderate or high fit (5.8% vs. 3.0% or 3.9%, respectively); with a similar pattern seen for prevalence of osteopenia (T-score > -2.5 and ≤ -1.0 at the FN) (47.5% vs. 46.4% or 44.8%, respectively). Higher age and lower weight were associated with low BMD. Fully adjusted logistic regression models showed an inverse association between CRF and low BMD of the FN. For T-score ≤ -1.0, the primary outcome, the odds ratio (OR) was 0.50 (95% confidence interval [CI] 0.32-0.79) for moderate fitness, and OR of 0.32 (95% CI 0.21-0.51) for high fitness was seen. For T-score ≤ -2.5 at the FN, OR was 0.30 (95% CI 0.11-0.80) for moderate fitness, and OR was 0.29 (95% CI 0.12-0.71) for high fitness.

CONCLUSION

Increased CRF levels are associated with reduced risk for low bone density in postmenopausal women.

Effects of Combined Resistance and Endurance Training Versus Resistance Training Alone on Strength, Exercise Capacity, and Quality of Life in Patients With COPD

PURPOSE

To compare the effects of 12-week training periods (2 d·wk) involving resistance training only with the effects of 12-week training periods involving combined resistance (once weekly) and endurance (once weekly) training on strength, endurance performance, and quality of life.

METHODS

Thirty-six patients with moderate-to-severe chronic obstructive pulmonary disease were randomized to combined training (REG), resistance training alone (RG), or control (CG) groups. Patients were tested for maximal strength of the upper and lower extremities, power output of the lower extremities, maximal (Wmax) and submaximal exercise capacity, performance on a 6-minute walk test (6MWT), and quality of life.

RESULTS

REG and RG induced similar maximal strength gains. Muscle power increased 19% (P ≤ .01) and Wmax improved 13% (P < .05) in REG. Reductions (P < .05) in the heart rate and blood lactate at a given submaximal workload were observed in REG. Improvements in 6MWT and quality of life were similar in both training groups.

CONCLUSIONS

Compared with a twice-weekly resistance training program, the combination of once-weekly resistance and once-weekly endurance training not only produced similar gains in maximal strength, 6MWT performance, and quality of life but also produced improvements in muscle power and endurance performance. These findings may have implications for the prescription of resistance and endurance exercise for patients with chronic obstructive pulmonary disease.

A Novel Exercise Initiative for Seniors to Improve Balance and Physical Function

OBJECTIVE

To investigate the feasibility, effectiveness, and short-term effects of an exercise intervention using a novel exercise park in improving seniors' balance, physical function, and quality of life.

METHOD

Randomized controlled trial with pre- and post-intervention design (baseline and 18-week intervention) was used. Outcome measures included measures of balance, strength, and function, as well as quality of life and fear of falling. MANCOVA was used to assess differences between groups (control and exercise intervention) over time.

RESULTS

Intervention group showed significant improvement on single leg stance ( p = .02, 95% confidence interval [CI] = [-8.35, -0.549]), knee strength ( p < .01, 95% CI = [-29.14, -5.86]), 2-min walk ( p = 0.02, 95% CI = [-19.13, -0.859]), and timed sit to stand ( p = .03, 95% CI = [-2.26, -0.143]) tests.

DISCUSSION

The exercise park program improved physical function and had high adherence and participation rate. Such intervention has been shown to be safe and therefore might enhance participation in exercise programs for older adults.

Similar enhancement of BK(Ca) channel function despite different aerobic exercise frequency in aging cerebrovascular myocytes

Aerobic exercise showed beneficial influence on cardiovascular systems in aging, and mechanisms underlying vascular adaption remain unclear. Large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels play critical roles in regulating cellular excitability and vascular tone. This study determined the effects of aerobic exercise on aging-associated functional changes in BK(Ca) channels in cerebrovascular myocytes, Male Wistar rats aged 20-22 months were randomly assigned to sedentary (O-SED), low training frequency (O-EXL), and high training frequency group (O-EXH). Young rats were used as control. Compared to young rats, whole-cell BK(Ca) current was decreased, and amplitude of spontaneous transient outward currents were reduced. The open probability and Ca(2+)/voltage sensitivity of single BK(Ca) channel were declined in O-SED, accompanied with a reduction of tamoxifen-induced BK(Ca) activation; the mean open time of BK(Ca) channels was shortened whereas close time was prolonged. Aerobic exercise training markedly alleviated the aging-associated decline independent of training frequency. Exercise three times rather than five times weekly may be a time and cost-saving training volume required to offer beneficial effects to offset the functional declines of BK(Ca) during aging.

Sarcopenia, Frailty, and Diabetes in Older Adults

Populations are aging and the prevalence of diabetes mellitus is increasing tremendously. The number of older people with diabetes is increasing unexpectedly. Aging and diabetes are both risk factors for functional disability. Thus, increasing numbers of frail or disabled older patients with diabetes will increase both direct and indirect health-related costs. Diabetes has been reported as an important risk factor of developing physical disability in older adults. Older people with diabetes have lower muscle mass and weaker muscle strength. In addition, muscle quality is poorer in diabetic patients. Sarcopenia and frailty have a common soil and may share a similar pathway for multiple pathologic processes in older people. Sarcopenia is thought to be an intermediate step in the development of frailty in patients with diabetes. Thus, early detection of sarcopenia and frailty in older adults with diabetes should be routine clinical practice to prevent frailty or to intervene earlier in frail patients.

Efficacy of recreational football on bone health, body composition, and physical functioning in men with prostate cancer undergoing androgen deprivation therapy: 32-week follow-up of the FC prostate randomised controlled trial

Androgen deprivation therapy (ADT) for prostate cancer (PCa) impairs musculoskeletal health. We evaluated the efficacy of 32-week football training on bone mineral density (BMD) and physical functioning in men undergoing ADT for PCa. Football training improved the femoral shaft and total hip BMD and physical functioning parameters compared to control.

INTRODUCTION

ADT is a mainstay in PCa management. Side effects include decreased bone and muscle strength and increased fracture rates. The purpose of the present study was to evaluate the effects of 32 weeks of football training on BMD, bone turnover markers (BTMs), body composition, and physical functioning in men with PCa undergoing ADT.

METHODS

Men receiving ADT >6 months (n = 57) were randomly allocated to a football training group (FTG) (n = 29) practising 2-3 times per week for 45-60 min or to a standard care control group (CON) (n = 28) for 32 weeks. Outcomes were total hip, femoral shaft, femoral neck and lumbar spine (L2-L4) BMD and systemic BTMs (procollagen type 1 amino-terminal propeptide, osteocalcin, C-terminal telopeptide of type 1 collagen). Additionally, physical functioning (postural balance, jump height, repeated chair rise, stair climbing) was evaluated.

RESULTS

Thirty-two-week follow-up measures were obtained for FTG (n = 21) and for CON (n = 20), respectively. Analysis of mean changes from baseline to 32 weeks showed significant differences between FTG and CON in right (0.015 g/cm(2)) and left (0.017 g/cm(2)) total hip and in right (0.018 g/cm(2)) and left (0.024 g/cm(2)) femoral shaft BMD, jump height (1.7 cm) and stair climbing (-0.21 s) all in favour of FTG (p < 0.05). No other significant between-group differences were observed.

CONCLUSIONS

Compared to standard care, 32 weeks of football training improved BMD at clinically important femoral sites and parameters of physical functioning in men undergoing ADT for PCa.

Impact of a brief exercise program on the physical and psychosocial health of prostate cancer survivors: A pilot study

AIM

It is well established that exercise is beneficial for prostate cancer survivors. The challenge for health professionals is to create effective strategies to encourage survivors to exercise in the community. Many community exercise programs are brief in duration (e.g. <5 exercise sessions); whilst evidence for the efficacy of exercise within the literature are derived from exercise programs ≥8 weeks in duration, it is unknown if health benefits can be obtained from a shorter program. This study examined the effect of a four-session individualized and supervised exercise program on the physical and psychosocial health of prostate cancer survivors.

METHODS

Fifty-one prostate cancer survivors (mean age 69±7 years) were prescribed 1 h, individualized, supervised exercise sessions once weekly for 4 weeks. Participants were encouraged to increase their physical activity levels outside of the exercise sessions. Objective measures of muscular strength, exercise capacity, physical function and flexibility; and self-reported general, disease-specific and psychosocial health were assessed at baseline and following the intervention.

RESULTS

Improvements were observed in muscle strength (leg press 17.6 percent; P < 0.001), exercise capacity (400-m walk 9.3 percent; P < 0.001), physical function (repeated chair stands 20.1 percent, usual gait speed 19.3 percent, timed up-and-go 15.0 percent; P < 0.001), flexibility (chair sit and reach +2.9 cm; P < 0.001) and positive well-being (P = 0.014) following the exercise program.

CONCLUSION

A four-session exercise program significantly improved the muscular strength, exercise capacity, physical function and positive well-being of prostate cancer survivors. This short-duration exercise program is safe and feasible for prostate cancer survivors and a randomized controlled trial is now required to determine whether a similar individualized exercise regimen improves physical health and mental well-being over the short, medium and long term.

Effects of a balance training program using a foam rubber pad in community-based older adults: a randomized controlled trial

BACKGROUND AND PURPOSE

Exercise programs aimed at improving balance are effective in fall prevention for older adults. Guidelines indicate that unstable elements should be integrated in balance training with this population. Balance training on an unstable surface facilitates proprioception mediated by skin receptors in the soles of the feet and by mechanoreceptors in the joints and muscles. This randomized controlled trial examined whether balance training performed using a foam rubber pad was more beneficial than balance training performed on a stable flat surface in older adults.

METHODS

Older adults using Japanese community day centers once or twice per week were enrolled in this trial. In total, 93 participants were randomized to 1 of 3 groups: foam rubber exercise group (n = 32), stable surface exercise group (n = 31), and control group (n = 30). Participants in the foam rubber and stable surface exercise groups attended a 60-minute exercise class once a week for 4 months and followed a home-based exercise routine. Outcome measures were the following performance tests: the one-leg standing test (OLST), the chair standing test, the timed up-and-go test (TUGT), and the tandem-stance test (TST). These assessments were conducted before the intervention, and at 1, 2, 3, and 4 months after starting the intervention.

RESULTS

There were group × time interactions (P < 0.001) for all performance tests. The foam rubber exercise group showed significant improvements in the OLST, TST, and TUGT at 1 to 4 months compared with the control group (P < 0.02). The foam rubber exercise group also showed significant improvements in the OLST and TST at 2 and 3 months compared with the stable surface exercise group (P < 0.02). Within the foam rubber exercise group, the OLST, TUGT, and TST, at 1 to 4 months, were significantly improved compared with before the intervention (P < 0.01). Within the stable surface exercise group, the TUGT and TST, at 3 and 4 months, were significantly improved compared with before the intervention (P < 0.01).

CONCLUSIONS

This study confirms that balance training in older adults performed using a foam rubber pad is effective for improving balance ability, and that this improvement occurs 2 months earlier compared with balance training performed on a stable surface. These findings suggest that balance training performed using a foam rubber pad is beneficial to clients and service providers because the programs improve physical functioning with a reduced number of exercise sessions.

Dose-Response Relationships of Resistance Training in Healthy Old Adults: A Systematic Review and Meta-Analysis

BACKGROUND

Resistance training (RT) is an intervention frequently used to improve muscle strength and morphology in old age. However, evidence-based, dose-response relationships regarding specific RT variables (e.g., training period, frequency, intensity, volume) are unclear in healthy old adults.

OBJECTIVES

The aims of this systematic review and meta-analysis were to determine the general effects of RT on measures of muscle strength and morphology and to provide dose-response relationships of RT variables through an analysis of randomized controlled trials (RCTs) that could improve muscle strength and morphology in healthy old adults.

DATA SOURCES

A computerized, systematic literature search was performed in the electronic databases PubMed, Web of Science, and The Cochrane Library from January 1984 up to June 2015 to identify all RCTs related to RT in healthy old adults.

STUDY ELIGIBILITY CRITERIA

The initial search identified 506 studies, with a final yield of 25 studies. Only RCTs that examined the effects of RT in adults with a mean age of 65 and older were included. The 25 studies quantified at least one measure of muscle strength or morphology and sufficiently described training variables (e.g., training period, frequency, volume, intensity).

STUDY APPRAISAL AND SYNTHESIS METHODS

We quantified the overall effects of RT on measures of muscle strength and morphology by computing weighted between-subject standardized mean differences (SMDbs) between intervention and control groups. We analyzed the data for the main outcomes of one-repetition maximum (1RM), maximum voluntary contraction under isometric conditions (MVC), and muscle morphology (i.e., cross-sectional area or volume or thickness of muscles) and assessed the methodological study quality by Physiotherapy Evidence Database (PEDro) scale. Heterogeneity between studies was assessed using I2 and χ2 statistics. A random effects meta-regression was calculated to explain the influence of key training variables on the effectiveness of RT in terms of muscle strength and morphology. For meta-regression, training variables were divided into the following subcategories: volume, intensity, and rest. In addition to meta-regression, dose-response relationships were calculated independently for single training variables (e.g., training frequency).

RESULTS

RT improved muscle strength substantially (mean SMDbs = 1.57; 25 studies), but had small effects on measures of muscle morphology (mean SMDbs = 0.42; nine studies). Specifically, RT produced large effects in both 1RM of upper (mean SMDbs = 1.61; 11 studies) and lower (mean SMDbs = 1.76; 19 studies) extremities and a medium effect in MVC of lower (mean SMDbs = 0.76; four studies) extremities. Results of the meta-regression revealed that the variables "training period" (p = 0.04) and "intensity" (p < 0.01) as well as "total time under tension" (p < 0.01) had significant effects on muscle strength, with the largest effect sizes for the longest training periods (mean SMDbs = 2.34; 50-53 weeks), intensities of 70-79% of the 1RM (mean SMDbs = 1.89), and total time under tension of 6.0 s (mean SMDbs = 3.61). A tendency towards significance was found for rest in between sets (p = 0.06), with 60 s showing the largest effect on muscle strength (mean SMDbs = 4.68; two studies). We also determined the independent effects of the remaining training variables on muscle strength. The following independently computed training variables are most effective in improving measures of muscle strength: a training frequency of two sessions per week (mean SMDbs = 2.13), a training volume of two to three sets per exercise (mean SMDbs = 2.99), seven to nine repetitions per set (mean SMDbs = 1.98), and a rest of 4.0 s between repetitions (SMDbs = 3.72). With regard to measures of muscle morphology, the small number of identified studies allowed us to calculate meta-regression for the subcategory training volume only. No single training volume variable significantly predicted RT effects on measures of muscle morphology. Additional training variables were independently computed to detect the largest effect for the single training variable. A training period of 50-53 weeks, a training frequency of three sessions per week, a training volume of two to three sets per exercise, seven to nine repetitions per set, a training intensity from 51 to 69% of the 1RM, a total time under tension of 6.0 s, a rest of 120 s between sets, and a rest of 2.5 s between repetitions turned out to be most effective.

LIMITATIONS

The current results must be interpreted with caution because of the poor overall methodological study quality (mean PEDro score 4.6 points) and the considerable large heterogeneity (I2) = 80%, χ2 = 163.1, df = 32, p < 0.01) for muscle strength. In terms of muscle morphology, our search identified nine studies only, which is why we consider our findings preliminary. While we were able to determine a dose-response relationship based on specific individual training variables with respect to muscle strength and morphology, it was not possible to ascertain any potential interactions between these variables. We recognize the limitation that the results may not represent one general dose-response relationship.

CONCLUSIONS

This systematic literature review and meta-analysis confirmed the effectiveness of RT on specific measures of upper and lower extremity muscle strength and muscle morphology in healthy old adults. In addition, we were able to extract dose-response relationships for key training variables (i.e., volume, intensity, rest), informing clinicians and practitioners to design effective RTs for muscle strength and morphology. Training period, intensity, time under tension, and rest in between sets play an important role in improving muscle strength and morphology and should be implemented in exercise training programs targeting healthy old adults. Still, further research is needed to reveal optimal dose-response relationships following RT in healthy as well as mobility limited and/or frail old adults.

Effect of resistance training with different frequencies and detraining on muscular strength and oxidative stress biomarkers in older women

The aim of this study was to compare the effect of resistance training (RT) performed with different frequencies followed by a detraining period on muscular strength and oxidative stress (OS) biomarkers in older women. Twenty-seven physically independent women (68.8 ± 4.8 years, 69.1 ± 14.3 kg, 156.0 ± 6.5 cm, and 28.3 ± 4.9 to kg.m(-2)) were randomly assigned to perform a RT program for 2 or 3 days per week (G2X = 13 vs. G3X = 14) for 12 weeks followed by 12 weeks of detraining period. One repetition maximum (1RM) tests were used as measures of muscular strength (three exercises, three attempts for each exercise, 3-5 min of rest between attempts, and 5 min of rest between exercises). Advanced oxidized protein products (AOPP) and total radical-trapping antioxidant parameter (TRAP) were used as oxidative stress indicators. Both groups increased muscular strength after 12 weeks of training (P < 0.05) in chest press (G2X = +11.9 % vs. G3X = +27.5 %, P < 0.05), knee extension (G2X = +18.4 % vs. G3X = +16.7 %, P > 0.05), and preacher curl (G2X = +37.6 % vs. G3X = +36.7 %, P > 0.05). On the other hand, 12 weeks of detraining were not sufficient to eliminate the major effects produced by RT on muscular strength, although a significant decrease (P < 0.05) has been observed for chest press (G3X = -9.1 % vs. G2X = -10.2 %, P > 0.05), knee extension (G2X = -14.9 % vs. G3X = -12.1 %, P > 0.05), and preacher curl (G2X = -20.5 % vs. G3X = -17.4 %, P > 0.05). Pre- to post-training, both groups showed significant (P < 0.05) increases in TRAP (G2X = +6.9 % vs. G3X = +15.1 %) with no statistical significant difference between the groups (P > 0.05), and the scores remained elevated compared to pre-training after 12 weeks of detraining. AOPP was not changed by RT or detraining (P > 0.05). The results suggest that a 12-week RT program with a frequency of 2 days per week may be sufficient to improve muscular strength and OS in older women and detraining for 12 weeks does not completely reverse the changes induced by RT.

Assessment of anticancer-treatment outcome in patients with metastatic castration-resistant prostate cancer-going beyond PSA and imaging, a systematic literature review

BACKGROUND

In the past years, there has been significant progress in anticancer drug development for patients with metastatic castration-resistant prostate cancer (CRPC). However, the current instruments to assess clinical treatment response have limitations and may not sufficiently reflect patient benefit. Our objective was to systematically identify tools to evaluate both patient benefit and clinical anticancer-treatment response as basis for an international consensus process and development of a specific pragmatic instrument for men with CRPC.

METHODS

PubMed, Embase and CINAHL were searched to identify currently available tools to assess anticancer-treatment benefit, other than standard imaging procedures and prostate-specific antigen measurements, namely quality of life (QoL), detailed pain assessment, physical function and objective measures of other complex cancer-related syndromes in patients with CRPC. Additionally, all CRPC phase III trials published in the last 5 years were reviewed as well as studies using physical function tools in a general cancer population. The PRIMSA statement was followed for the systematic review process.

RESULTS

The search generated 1096 hits, 185 full-text papers were screened and finally 73 publications were included. Additional 89 publications were included by hand-search. We identified a total of 98 tools used in CRPC trials and grouped these into three categories: 22 tools assessing QoL domains and subgroups, 47 tools for pain assessment and 29 tools for objective measures, mainly physical function and assessment of skeletal disease burden.

CONCLUSION

A wide variety of assessment tools and also efforts to standardize and harmonize patient-reported outcomes and pain assessment were identified. However, the specific needs of the increasing CRPC population living longer with their incurable cancer are insufficiently captured and objective physical outcome measures are under-represented. In the age of new anticancer drug targets and principles, new methods to monitor patient relevant outcomes of antineoplastic therapy are of utmost importance.

Differential effects of water-based exercise on the cognitive function in independent elderly adults

BACKGROUND

Physical exercise has been reported to be the most effective method to improve cognitive function and brain health, but there is as yet no research on the effect of water-based exercise.

AIMS

The aim of the present study was to compare the effects of water-based exercise with and without cognitive stimuli on cognitive and physical functions.

METHODS

The design is a single-blind randomized controlled study. Twenty-one participants were randomly assigned to a normal water-based exercise (Nor-WE) group or a cognitive water-based exercise (Cog-WE) group. The exercise sessions were divided into two exercise series: a 10-min series of land-based warm-up, consisting of flexibility exercises, and a 50-min series of exercises in water. The Nor-WE consisted of 10 min of walking, 30 min of strength and stepping exercise, including stride over, and 10 min of stretching and relaxation in water. The Cog-WE consisted of 10 min of walking, 30 min of water-cognitive exercises, and 10 min of stretching and relaxation in water. Cognitive function, physical function, and ADL were measured before the exercise intervention (pre-intervention) and 10 weeks after the intervention (post-intervention).

RESULTS

Participation in the Cog-WE performed significantly better on the pegboard test and the choice stepping reaction test and showed a significantly improved attention, memory, and learning, and in the general cognitive function (measured as the total score in the 5-Cog test). Participation in the Nor-WE dramatically improved walking ability and lower limb muscle strength.

CONCLUSION

Our results reveal that the benefits elderly adults may obtain from water-based exercise depend on the characteristics of each specific exercise program. These findings highlight the importance of prescription for personalized water-based exercises to elderly adults to improve cognitive function.

Effects of different resistance training frequencies on flexibility in older women

OBJECTIVE

The main purpose of the investigation reported here was to analyze the effect of resistance training (RT) performed at different weekly frequencies on flexibility in older women.

PARTICIPANTS AND METHODS

Fifty-three older women (≥60 years old) were randomly assigned to perform RT either two (n=28; group "G2x"), or three (n=25; group "G3x") times per week. The RT program comprised eight exercises in which the participants performed one set of 10-15 repetitions maximum for a period of 12 weeks. Anthropometric, body-composition, and flexibility measurements were made at baseline and post-study. The flexibility measurements were obtained by a fleximeter.

RESULTS

A significant group-by-time interaction (P<0.01) was observed for frontal hip flexion, in which G3x showed a higher increase than G2x (+12.8% and +3.0%, respectively). Both groups increased flexibility in cervical extension (G2x=+19.1%, G3x=+20.0%), right hip flexion (G2x=+14.6%, G3x=+15.9%), and left hip flexion (G2x=+25.7%, G3x=+19.2%), with no statistical difference between groups. No statistically significant differences were noted for the increase in skeletal muscle mass between training three versus two times a week (+7.4% vs +4.4%, respectively).

CONCLUSION

Twelve weeks of RT improves the flexibility of different joint movements in older women, and the higher frequency induces greater increases for frontal hip flexion.

Urine creatinine-based estimates of fat-free mass in community-dwelling older persons: the Rancho Bernardo study

OBJECTIVES

To determine whether a previously developed and externally validated equation using common variables (demographics and weight) that are important determinants of muscle mass to estimate 24-hour urine creatinine excretion rate (eCER) is associated with muscle mass and whether spot urine creatinine (UCr) provides similar estimates of muscle mass.

DESIGN

Observational cross-sectional cohort study.

SETTING

The Rancho Bernardo Study, San Diego, California.

SUBJECTS

A total of 1,371 Caucasian, middle class, community-dwelling older adults.

INTERVENTION

Morning spot UCr and fat-free mass (FFM) by dual-energy x-ray absorptiometry were measured. eCER was calculated: eCER (mg/day) = 879.89 + 12.51 × weight (kilogram) - 6.19 × age + 34.51 if black - 379.42 if female. Pearson correlation coefficients and linear regression were used to determine strengths of association of eCER and spot UCr with FFM.

RESULTS

Mean age was 70 years, and 58% were women. eCER was strongly correlated with FFM (r = 0.95, P < .001), a correlation that was superior to that of spot UCr (r = 0.40, P < .001).

CONCLUSIONS

An equation incorporating age, weight, sex, and race to estimate eCER is highly correlated with FFM in community-dwelling older persons and provides a more precise estimate than spot UCr. A simple screening tool for sarcopenia in older persons may allow interventions to maintain or improve muscle mass. Future studies should evaluate whether eCER predicts sarcopenia-related frailty and mortality in older persons.

Football training improves lean body mass in men with prostate cancer undergoing androgen deprivation therapy

Androgen deprivation therapy (ADT) remains a cornerstone in the management of patients with prostate cancer (PCa) despite adverse effects on body composition and functional parameters. We compared the effects of football training with standard care in PCa patients managed with ADT (> 6 months). Fifty-seven men aged 67 (range: 43-74) were randomly assigned to a football group (FG, n = 29) or a usual care control group (CON, n = 28). The primary outcome was change in lean body mass (LBM) assessed by dual-energy X-ray absorptiometry scanning. Secondary outcomes included changes in knee-extensor muscle strength (one repetition maximum), fat percentage, and maximal oxygen uptake (VO2max ). Mean heart rate during training was 137.7 (standard deviation 13.7) bpm or 84.6 (3.9)% HRmax. In FG, LBM increased by 0.5 kg [95% confidence interval (CI) 0.1-0.9; P = 0.02] with no change in CON (mean group difference 0.7 kg; 95% CI 0.1-1.2; P = 0.02). Also, muscle strength increased in FG (8.9 kg; 95% CI 6.0-11.8; P < 0.001) with no change in CON (mean group difference 6.7 kg; 95% CI 2.8-10.7; P < 0.001). In FG, VO2max increased (1.0 mL/kg/min; 95% CI 0.2-1.9; P = 0.02) and fat percentage tended to decrease (0.7%; 95%CI 1.3-0.0; P = 0.06), but these changes were not significantly different from CON. In conclusion, football training over 12 weeks improved LBM and muscle strength compared with usual care in men with prostate cancer receiving ADT.

Effects of a combined physical training and nutrition intervention on physical performance and health-related quality of life in prefrail older women living in the community: a randomized controlled trial

OBJECTIVES

The purpose of this study was to examine whether a 12-week combined physical exercise training and nutritional intervention improves physical performance and enhances health-related quality of life (HRQOL) among prefrail elderly women living in the community.

DESIGN

This was a randomized controlled trial in which participants were recruited and randomly assigned to the exercise and nutrition group (EN, n = 30), exercise only group (E, n = 28), and control group (C, n = 31).

SETTING

Group training classes were held at a research center in Itabashi Ward, Tokyo, Japan.

PARTICIPANTS

Eighty-nine prefrail women aged 70 years or older.

INTERVENTION

The EN group participated in an exercise training and nutritional program (cooking class) once a week, and the E group participated in the exercise training program only.

MEASUREMENTS

Outcome measures that included physical performance (handgrip strength, balance, walking speed) and HRQOL (Medical Outcomes Study 36-Item Short Form Health Survey) were obtained at entry, the end of the 12-week intervention, and 6 months after completion of the intervention program.

RESULTS

At the end of the 12-week intervention, significant improvements in the physical component summary score and 3 (role physical, bodily pain, role emotional) of the 8 domains of the Medical Outcomes Study 36-Item Short Form Health Survey were observed in the EN group. The E group exhibited a significantly increased handgrip strength at postintervention. The positive effects, however, were not maintained at 6-month follow-up, but were reduced.

CONCLUSIONS

The combined physical exercise training and nutritional intervention program has beneficial effects on several domains of HRQOL and handgrip strength in prefrail elderly women living in the community. However, further studies are needed to examine approaches that facilitate maintenance of the improved outcomes by combined exercise training and nutritional intervention.

Effects of single vs. multiple-set short-term strength training in elderly women

The strength training has been shown to be effective for attenuating the age-related physiological decline. However, the adequate volume of strength training volume adequate to promote improvements, mainly during the initial period of training, still remains controversial. Thus, the purpose of this study was to compare the effects of a short-term strength training program with single or multiple sets in elderly women. Maximal dynamic (1-RM) and isometric strength, muscle activation, muscle thickness (MT), and muscle quality (MQ = 1-RM and MT quadriceps quotient) of the knee extensors were assessed. Subjects were randomly assigned into one of two groups: single set (SS; n = 14) that performed one set per exercise or multiple sets (MS; n = 13) that performed three-sets per exercise, twice weekly for 6 weeks. Following training, there were significant increases (p ≤ 0.05) in knee extension 1-RM (16.1 ± 12 % for SS group and 21.7 ± 7.7 % for MS group), in all MT (p ≤ 0.05; vastus lateralis, rectus femoris, vastus medialis, and vastus intermedius), and in MQ (p ≤ 0.05); 15.0 ± 12.2 % for SS group and 12.6 ± 7.2 % for MS group), with no differences between groups. These results suggest that during the initial stages of strength training, single- and multiple-set training demonstrate similar capacity for increasing dynamic strength, MT, and MQ of the knee extensors in elderly women.

Single- and multiple-set resistance training improves skeletal and respiratory muscle strength in elderly women

Introduction

Aging involves a progressive reduction of respiratory muscle strength as well as muscle strength.

Purpose

Compare the effects of resistance training volume on the maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), functional performance, and muscle strength in elderly women.

Methods

Thirty elderly women were randomly assigned to a group performing either single sets (1-SET) or three sets (3-SET) of exercises. The sit-to-stand test, MIP, MEP, and muscle strength were assessed before and after 24 training sessions. Progressive resistance training was performed two times per week for a total of 8–12 repetitions, using the main muscle groups of the upper and lower limbs.

Results

The main results showed that the participants significantly increased their MEP (P<0.05; 1-SET: 34.6%; 3-SET: 35.8%) and MIP (P<0.05; 1-SET: 13.7%; 3-SET: 11.2%). Both groups also improved in the sit-to-stand test (P<0.05; 1-SET: 10.6%; 3-SET: 17.1%). After 24 training sessions, muscle strength also significantly increased (P<0.0001; 40%–80%) in both groups. An intergroup comparison did not show any statistically significant differences between the groups in any of the parameters analyzed.

Conclusion

Single- and multiple-set resistance training programs increased MIP, MEP, muscle strength, and sit-to-stand test performance in elderly women after 24 sessions of training. In conclusion, our results suggested that elderly women who are not in the habit of physical activity may start with single-set resistance training programs as a short-term strategy for the maintenance of health.

Mechanistic investigation of adult myotube response to exercise and drug treatment in vitro using a multiplexed functional assay system

The ability to accurately measure skeletal muscle functional performance at the single-cell level would be advantageous for exercise physiology studies and disease modeling applications. To that end, this study characterizes the functional response of individual skeletal muscle myotubes derived from adult rodent tissue to creatine treatment and chronic exercise. The observed improvements to functional performance in response to these treatments appear to correlate with alterations in hypertrophic and mitochondrial biogenesis pathways, supporting previously published in vivo and in vitro data, which highlights the role of these pathways in augmenting skeletal muscle output. The developed system represents a multiplexed functional in vitro assay capable of long-term assessment of contractile cellular outputs in real-time that is compatible with concomitant molecular biology analysis. Adoption of this system in drug toxicity and efficacy studies would improve understanding of compound activity on physical cellular outputs and provide more streamlined and predictive data for future preclinical analyses.