Efficacy Of Resistance Training Research Articles

Comparative Efficacy of Different Protein Supplements on Muscle Mass, Strength, and Physical Indices of Sarcopenia among Community-Dwelling, Hospitalized or Institutionalized Older Adults Undergoing Resistance Training: A Network Meta-Analysis of Randomized Controlled Trials.

Aging-related sarcopenia exerts harmful impacts on muscle mass, strength, and physical mobility. Protein supplementation has been demonstrated to augment efficacy of resistance training (RT) in elderly. This study compared the relative effects of different protein supplements on muscle mass, strength, and mobility outcomes in middle-aged and older individuals undergoing RT. A comprehensive search of online databases was performed to identify randomized controlled trials (RCTs) examining the efficacy of protein supplement plus RT in untrained community-dwelling adults, hospitalized, or institutionalized residents who suffered acute or chronic health conditions. Network meta-analysis (NMA) was performed using a frequentist method for all analyses. Treatment effects for main outcomes were expressed as standard mean difference (SMD) with 95% confidence interval (CI). We used the surface-under-the cumulative-ranking (SUCRA) scores to rank probabilities of effect estimation among all identified treatments. Meta-regression analyses were performed to identify any relevant moderator of the treatment efficacy and results were expressed as β with 95% credible interval (CrI). We finally included 78 RCTs (5272 participants) for analyses. Among the six protein sources identified in this NMA, namely whey, milk, casein, meat, soy, and peanut, whey supplement yielded the most effective treatments augmenting efficacy of RT on muscle mass (SMD = 1.29, 95% CI: 0.96, 1.62; SUCRA = 0.86), handgrip strength (SMD = 1.46, 95% CI: 0.92, 2.00; SUCRA = 0.85), and walking speed (SMD = 0.73, 95% CI: 0.39, 1.07; SUCRA = 0.84). Participant's health condition, sex, and supplementation dose were significant factors moderating the treatment efficacy on muscle mass (β = 0.74; 95% CrI: 0.22, 1.25), handgrip strength (β = -1.72; 95% CrI: -2.68, -0.77), and leg strength (β = 0.76; 95% CrI: 0.06, 1.47), respectively. Our findings suggest whey protein yields the optimal supplements to counter sarcopenia in older individuals undergoing RT.

Efficacy Of Resistance Training As An Aid To Smoking Cessation In People Living With HIV: A Secondary Analysis

Efficacy Of Resistance Training As An Aid To Smoking Cessation In People Living With HIV: A Secondary Analysis

Efficacy of resistance training in hypoxia on muscle hypertrophy and strength development: a systematic review with meta-analysis

A systematic review and meta-analysis was conducted to determine the effects of resistance training under hypoxic conditions (RTH) on muscle hypertrophy and strength development. Searches of PubMed-Medline, Web of Science, Sport Discus and the Cochrane Library were conducted comparing the effect of RTH versus normoxia (RTN) on muscle hypertrophy (cross sectional area (CSA), lean mass and muscle thickness) and strength development [1-repetition maximum (1RM)]. An overall meta-analysis and subanalyses of training load (low, moderate or high), inter-set rest interval (short, moderate or long) and severity of hypoxia (moderate or high) were conducted to explore the effects on RTH outcomes. Seventeen studies met inclusion criteria. The overall analyses showed similar improvements in CSA (SMD [CIs] = 0.17 [− 0.07; 0.42]) and 1RM (SMD = 0.13 [0.0; 0.27]) between RTH and RTN. Subanalyses indicated a small effect on CSA for shorter inter-set rest intervals, moderate hypoxia and moderate loads favoring RTH. Moreover, a medium effect for longer inter-set rest intervals and a trivial to small effect for severe hypoxia and moderate loads favoring RTH was found on 1RM. Evidence suggests that RTH employed with moderate loads (60–80% 1RM) enhances both hypertrophy and strength. Hypertrophy appears to benefit from shorter (≤ 60 s) inter-set rest intervals during RTH while greater gains in strength are achieved with longer rest intervals (≥ 120 s). The use of moderate hypoxia (14.3–16% FiO2) seems to be somewhat beneficial to hypertrophy but not strength. Further research is required with greater standardization of protocols to draw stronger conclusions on the topic.

Effect of Resistance Training on Body Composition, Hemodynamic Parameters and Exercise Tolerance among Patients with Coronary Artery Disease: A Systematic Review

Effectiveness and safety of Resistance Training in treating various Cerebrovascular Disease diagnoses have drawn attention in recent years. Patients suffering with coronary artery disease should be offered individually tailored Resistance Training in their exercise regimen. Resistance Training was developed to help individuals with their functional status, mobility, physical performance, and muscle strength. The objective of this review was to collect, summarize and present information on the state of science focusing on usefulness, viability, safety and efficacy of Resistance Training in treating coronary artery disease and enhancing the aerobic capacity and improving overall health-related quality of life. The review is prepared in accordance with Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Searches were conducted in Cochrane Library, PubMed/MEDLINE, PEDro and Scopus database. PEDro scale was used for methodological quality assessment of included studies. Two independent reviewers determined the inclusion criteria of studies by classifying interventions based on core components, outcome measures, diagnostic population and rated the quality of evidence and strength of recommendations using GRADE criteria. Total 13 studies with 1025 patients were included for the detailed analysis. Findings emphasize the importance of assessing effectiveness and safety of Resistance Training in individuals with coronary artery disease. Patient specific designed exercise programs as Resistance Training targets at enhancing patients' exercise tolerance, improves hemodynamic response and muscular strength with reduction in body fat composition. Resistance Training is an effective exercise that should be incorporated to counteract the loss of muscle strength, muscle mass, and physiological vulnerability, as well as to combat the associated debilitating effects on physical functioning, mobility and overall independence and Quality of Life during rehabilitation of patients with coronary artery disease.

Resistance Training in Patients With Coronary Artery Disease, Heart Failure, and Valvular Heart Disease: A REVIEW WITH SPECIAL EMPHASIS ON OLD AGE, FRAILTY, AND PHYSICAL LIMITATIONS.

Current guidelines recommend individually adapted resistance training (RT) as a part of the exercise regime in patients with cardiovascular diseases. The aim of this review was to provide insights into current knowledge and understanding of how useful, feasible, safe, and effective RT is in patients with coronary artery disease (CAD), heart failure (HF), and valvular heart disease (VHD), with particular emphasis on the role of RT in elderly and/or frail patients. A review based on an intensive literature search: systematic reviews and meta-analyses published in 2010 or later; recent studies not integrated into meta-analyses or systematic reviews; additional manual searches. The results highlight the evaluation of effects and safety of RT in patients with CAD and HF with reduced ejection fraction (HFrEF) in numerous meta-analyses. In contrast, few studies have focused on RT in patients with HF with preserved ejection fraction (HFpEF) or VHD. Furthermore, few studies have addressed the feasibility and impact of RT in elderly cardiac patients, and data on the efficacy and safety of RT in frail elderly patients are limited. The review results underscore the high prevalence of age-related sarcopenia, disease-related skeletal muscle deconditioning, physical limitations, and frailty in older patients with cardiovascular diseases (CVD). They underline the need for individually tailored exercise concepts, including RT, aimed at improving functional status, mobility, physical performance and muscle strength in older patients. Furthermore, the importance of the use of assessment tools to diagnose frailty, mobility/functional capacity, and physical performance in the elderly admitted to cardiac rehabilitation is emphasized.

Efficacy of resistance training during adjuvant chemotherapy and radiation therapy in cancer care: a systematic review and meta-analysis.

To determine the effect of resistance training during adjuvant chemotherapy and radiation therapy in cancer patients on measures of lean mass and muscle strength. Secondary aims were to analyse the prescription and tolerability of supervised resistance training in this population. EMBASE, Medline, CINAHL, Cochrane Library and Web of Science were searched from inception until 29 March 2021. Eligible randomised controlled trials (RCTs) examining supervised resistance training > 6 weeks duration during adjuvant chemotherapy and/or radiation therapy in cancer patients with objective measurement of muscle strength and/or lean mass were included. The meta-analysis was performed using Revman 5.4. A total of 1910 participants from 20 articles were included (mean age: 54 years, SD = 10) and the majority were female (76.5%). Resistance training was associated with a significant increase in upper body strength (standardised mean difference (SMD) = 0.57, 95% CI 0.36 to 0.79, I2 = 64%, P < 0.0001), lower body strength (SMD = 0.58, 95% CI 0.18 to 0.98, I2 = 91%, P = 0.005), grip strength (mean difference (MD) = 1.32, 95% CI 0.37 to 2.27, I2 = 0%, P < 0.01) and lean mass (SMD = 0.23, 95% CI 0.03 to 0.42, I2 = 0%, P = 0.02). A P value of < 0.05 was considered statistically significant. The quality of the studies included was moderate to high with low risk of bias as per the PEDro scale. Resistance training is an effective adjunct therapy to improve muscle strength and lean mass in cancer patients undergoing chemotherapy and/or radiation therapy. CRD42020180643.

Vitamin D supplementation does not enhance resistance training-induced gains in muscle strength and lean body mass in vitamin D deficient young men

Vitamin D (Vit-D) supplementation has been shown to increased muscle strength in young adults. It remains unclear if Vit-D supplementation enhances the efficacy of resistance training (RT). This study tested the hypothesis that Vit-D supplementation would enhance the RT-induced increases in muscle strength and lean body mass (LBM) in Vit-D deficient young men. Thirty-nine men (baseline serum 25(OH)D < 50nmol L‒1) were quasi-randomly assigned to one of the two groups that performed a 12-week supervised RT program concomitant with either Vit-D (8000IU daily; VD) or placebo (PLC) supplementation. During 12-week RT, energy and nutrient (except Vit-D) intake and training loads did not differ in the two groups. Serum 25(OH)D levels increased from 36.3 ± 9.2 to 142.4 ± 21.9nmol L‒1 (P < 0.05) in VD group and remained unchanged between 36.3 ± 8.9 and 29.4 ± 6.6nmol L‒1 (P > 0.05) in PLC group. Muscle strength (1-repetition maximum) increased (P < 0.05) to an equal extent in the two groups in 5 exercises performed on RT equipment, whereas strength gains in chest press and seated row were greater (P < 0.05) in PLC compared to VD group. Total and regional LBM (measured by DXA scan) increased (P < 0.05) equally in the two groups. Android fat mass decreased (P < 0.05) in VD group only. Vit-D supplementation does not enhance the efficacy of RT in terms of muscle strength and LBM gains in Vit-D deficient young healthy men.

The efficacy of resistance training in addition to usual care for adults with acute burn injury: A randomised controlled trial

Resistance training immediately after a burn injury has not been investigated previously. This randomised, controlled trial assessed the impact of resistance training on quality of life plus a number of physical, functional and safety outcomes in adults with a burn injury.Patients were randomly assigned to receive, in addition to standard physiotherapy, four weeks of high intensity resistance training (RTG) or sham resistance training (CG) three days per week, commenced within 72h of the burn injury. Outcome data was collected at six weeks, three and six months after burn injury. Quality of life at 6 months was the primary endpoint. Data analysis was an available cases analysis with no data imputed. Regression analyses were used for all longitudinal outcome data and between-group comparisons were used for descriptive analyses.Forty-eight patients were randomised resistance training (RTG) (n=23) or control group (CG) (n=25). The RTG demonstrated improved outcomes for the functional domain of the Burn Specific Health Scale-Brief (p=0.017) and the Quick Disability of Arm Shoulder and Hand (p<0.001). Between group differences were seen for C-reactive protein and retinol binding protein (p=0.001). Total quality of life scores, lower limb disability, muscle strength and volume were not seen to be different between groups (p>0.05).Resistance training in addition to usual rehabilitation therapy showed evidence of improving functional outcomes, particularly in upper limb burn injuries. Additionally, resistance training commenced acutely after a burn injury was not seen to be harmful to patients.

Effects Of Exercise Training On Circulating Branched-chain Amino Acid And Ketone Levels In Diabetics

PURPOSE: Elevated levels of circulating branched-chain amino acid (BCAA) and ketone bodies are recognized as biomarkers for cardiovascular disease (CVD) and other pathological conditions in type-2 diabetes mellitus (T2DM). Aerobic exercise interventions have previously shown decreases in levels of these markers, suggesting improved metabolic status and reduced risk of CVD. However, the efficacy of resistance training and concurrent programs in reducing BCAA and ketone body levels has not been well researched. METHODS: The current study was performed as a secondary analysis of the HART-D trial, a 9-month randomized, controlled exercise-training trial of 262 participants with T2DM. Participants were randomized to one of four groups; non-exercise control, aerobic training (AT), resistance training (RT), or a combined aerobic-resistance training (ATRT). The effects of the 9-month intervention on BCAAs (leucine, valine, and isoleucine) and ketone bodies (β-hydroxy-butyrate, BHB; acetoacetate, AcAc; and acetone) were examined across groups using generalized linear models adjusting for age, race, sex, and baseline BMI. We performed per-protocol analyses limited to all control participants (n=33) and only the exercise group participants who met the criteria of at least 70% adherence to their exercise prescription for 6 months (AT, n=62; RT, n=55; ATRR, n=64). RESULTS: AcAc (-17.6 ± 6.4, p=0.006), acetone (-10.6 ± 3.6, p=0.003), and total ketone body (-51.4 ± 20.0, p=0.01) concentrations (shown as mean ± SE in μmol/L) decreased in the RT group compared to the control group. Acetone also decreased in ATRT compared to the control group (-10.2 ± 3.5 μmol/L, p=0.004). CONCLUSIONS: Our results suggest that RT and ATRT programs could improve ketone body metabolism in those with T2DM.

The impact of malnutrition on efficacy of resistance training in community-dwelling older adults.

Few studies have focused on the effect of resistance training under conditions of malnutrition in older adults requiring long-term care. The purpose of this study was to investigate the influence of nutritional status in older adults on resistance training-induced changes in physical performance. A total of 91 community-dwelling older adults participated in 24weeks of resistance training. Participants used the 60% of one repetition maximum for three sets of 10 repetitions for resistance training. Short Physical Performance Battery (SPPB), Mini Nutritional Assessment Short Form (MNA-SF), Barthel Index, and grip strength were measured before and after the resistance training. The participants were classified into three groups according to the MNA-SF score at baseline (0 to 7 as malnutrition group, 8 to 11 as at risk group, and 12 to 14 as well-nourished group). In comparing the preintervention and postintervention changes in functional fitness of the groups, there was a significant Group×Time interaction for SPPB scores (F=11.59, p<0.01), 4-m walk speed (F=5.87, p<0.01), and grip strength (F=3.27, p<0.05). Multivariate logistic regression analysis showed that well-nourished group was significantly more likely to improvement of physical function (odds ratio 3.08, 95% confidence interval [1.54, 6.15], p<0.01). The results of study revealed that malnutrition was an independent negative factor of effects of resistance training in older adults. These results suggested that effects of resistance training may be affected by the nutritional state.

Resistance Training Is Associated With Higher Bone Mineral Density Among Young Adult Male Distance Runners Independent of Physiological Factors.

Duplanty, AA, Levitt, DE, Hill, DW, McFarlin, BK, DiMarco, NM, and Vingren, JL. Resistance training is associated with higher bone mineral density among young adult male distance runners independent of physiological factors. J Strength Cond Res 32(6): 1594-1600, 2018-Low bone mineral density (BMD) in male distance runners is common and could be modulated by a host of biomarkers involved in the dynamic balance of bone tissue. In contrast, resistance training can increase BMD; however, the efficacy of resistance training in protecting BMD in distance runners has not been elucidated. The aim of this study was to investigate the relationship between resistance training, testosterone and bone metabolism biomarker concentrations, and BMD in young adult male distance runners. Twenty-five apparently healthy men (23-32 years; mean ± SD: 25.9 ± 2.9 years; 1.77 ± 0.04 m; 75.4 ± 8.5 kg) were categorized into 1 of 3 groups: untrained control participants (CON; n = 8); nonresistance-trained runners (NRT; n = 8); or resistance-trained runners (RT; n = 9). Blood was collected and analyzed for concentrations of free and total testosterone and 14 bone metabolism biomarkers. Bone mineral density was assessed using dual-energy X-ray absorptiometry. At all measured sites, BMD was greater (p ≤ 0.05) for RT compared with NRT and CON. Vitamin D concentration was greater (p ≤ 0.05) in RT and NRT compared with CON. Concentrations of testosterone and remaining bone biomarkers did not differ between groups (p > 0.05). Resistance-trained runners had greater BMD than nonresistance-trained runners and untrained peers. This difference did not seem to be modulated by biomarkers that contribute to bone formation or resorption, indicating that differences in BMD are associated with habitual load-bearing exercise using external resistance. Runners should perform resistance exercise at least once per week because this is associated with greater BMD.

Heart rate recovery after physical exertion tests in elderly hypertensive patients undergoing resistance training

Abstract Introduction: Heart rate recovery after exercise is a valuable variable, associated with prognosis and it has been used as an indicator of cardiorespiratory fitness, especially in patients with heart disease, as hypertensive patients. Objective: This study aimed to analyze the response of heart rate recovery in elderly hypertensive patients undergoing a resistance training program. Methods: Sample was composed for 10 elderly women with a mean age of 70.7 ± 7.4 years. Exercise test and six-minute walk test were developed and we checked heart rate recovery in the 1st and 2nd minute post tests, before and after resistance training. Results: There was an increase in mean heart rate recovery in the analyzed minutes in both tests, but only in the 1st minute after six minutes walk test we found a significant increase (p = 0.02). Conclusion: The results suggest the efficacy of resistance training to improve cardiorespiratory fitness of elderly hypertensive patients.

Influence of nutritional status on efficacy of resistance training in community-dwelling older adults requiring long-term care

Influence of nutritional status on efficacy of resistance training in community-dwelling older adults requiring long-term care

Load-controlled moderate and high-intensity resistance training programs provoke similar strength gains in young women.

While current exercise guidelines recommend progressive, high-intensity resistance training (RT) to promote muscle hypertrophy and strength gains, controversy exists regarding the efficacy of lighter-load RT. We compared 2 work-matched RT interventions that differed in training intensity. Fifteen women underwent 10 weeks of unilateral knee extensor RT. One leg was trained at increasing intensity (intensity leg, InL, 50-80% 1-repetition maximum [1-RM]), and training progression in the contralateral leg (volume leg, VoL, 50% 1-RM) was based on increasing training volumes. Quadriceps muscle size (ultrasound, dual energy X-ray absorptiometry) and strength (isokinetic dynamometry) were assessed on 4 occasions. Both training programs induced significant, yet comparable increases in muscle size (InL: +4.6-12%, VoL: +3.1-11%) and strength (InL: +10-16%, VoL: +10-14%). Training at lower than commonly suggested intensities may be an equally effective alternative form of RT. Factors other than training intensity, such as the total mechanical work during training, may strongly affect the training response.

Effects of whey proteins and carbohydrates on the efficacy of resistance training in elderly people: double blind, randomised controlled trial

A few previous studies indicate that protein supplementation increases gains in muscle mass and strength during a resistance exercise program. The purpose of this study was to investigate whether whey protein supplementation results in greater increases in lean body mass, muscle strength and physical function in elderly individuals during 12 weeks of resistance exercise when compared to isocaloric carbohydrate supplementation. A total of 161 men and women, 65-91 years old, participated in a randomized, controlled, double-blind intervention study, involving dietary supplementation and a 12-week resistance exercise program, designed to increase muscle mass and strength of all major muscle groups. Participants exercised three times a week and received either 20 g of whey protein (n=83) or isocaloric carbohydrate (n=78) in liquid form immediately after each workout. Data were obtained at baseline and end point. The primary outcomes, lean body mass, strength and physical function increased significantly during the course of the study. Type of dietary supplementation did not influence gains in lean body mass (P=0.365), quadriceps strength (P=0.776) or performance during a 6-min walk (P=0.726) or a timed up-and-go test (P=0.151). Twenty participants discontinued the intervention. Ingestion of 20 g of whey protein immediately after resistance exercise three times per week, does not lead to greater gains in lean body mass, strength and physical function in elderly people with sufficient energy and protein intakes when compared to isocaloric carbohydrate.

IL-15 expression in skeletal muscle by resistance exercise training in type 2 diabetic rats

Introduction: Interleukin-15 (IL-15) is reported as a myokine that potentially regulates body composition and glucose metabolism. We investigated the effect of 8 weeks of resistance exercise training on endogenous IL-15 expression in skeletal muscle and glucose tolerance with concomitant changes of body composition in type 2 diabetic rats.Methods: 6 week-old Male ZDF (Zucker diabetic fatty) and ZLC (ZDF Lean Control) rats were randomly divided into 4 groups: sedentary ZDF (Con-ZDF), exercised ZDF (Ex-ZDF), sedentary ZLC (Con-ZLC), and exercised ZLC (Ex-ZLC). Ex-ZDF and Ex-ZLC rats were trained (once every 3 days for 8 weeks) to climb a 1.1-m vertical (80° incline) ladder with weights secured to their tail for progressive workload resistance exercise (the training was started at 50% or 70% of maximal weight of the last trial). Body weight, grip strength and intraperitoneal glucose tolerance test (IPGTT) were evaluated at every week. Body composition was analyzed by PET-CT (Positron Emission Tomography – Computed Tomography) and expression of IL-15 was measured using ELISA in extracted soleus muscle and tibialis anterior muscle.Results: After 8 weeks of resistance training, substantial reduction of the body weight was observed in Ex-ZDF compared to Con-ZDF. Grip strength was also significantly increased in Ex-ZDF compared to Con-ZDF after 8 weeks of regular strength exercise indicating the efficacy of resistance training. Glucose tolerance (IPGTT) was significantly improved in Ex-ZDF (p<0.05) compared to Con-ZDF showing more delayed drop in blood glucose level between 90 min and 120 min. Concurrently, the expression of IL-15 was significantly increased (p<0.01) after training especially in soleus muscle of Ex-ZDF compared to Con-ZDF and also there was a tendency of increase in IL-15 expression in tibialis anterior muscle in Ex-ZDF as well. Accordingly, PET-CT scan showed that muscle quality tended to be higher in Ex-ZDF than Con-ZDF while no significant difference between Con-ZLC and Ex-ZLC.Discussion: 8 weeks of progressive resistance exercise significantly improved glucose tolerance with the concomitant increase of IL-15 expression in hind-limb muscles suggesting that increased level of IL-15 in skeletal muscle by resistance exercise might be a potential mediator in glucose regulation of type 2 diabetes. Further study is needed to elucidate the mechanisms by which how increased IL-15 expression in skeletal muscle by resistance exercise exerts a favorable influence on impaired glucose metabolism in type 2 diabetes mellitus. Introduction: Interleukin-15 (IL-15) is reported as a myokine that potentially regulates body composition and glucose metabolism. We investigated the effect of 8 weeks of resistance exercise training on endogenous IL-15 expression in skeletal muscle and glucose tolerance with concomitant changes of body composition in type 2 diabetic rats. Methods: 6 week-old Male ZDF (Zucker diabetic fatty) and ZLC (ZDF Lean Control) rats were randomly divided into 4 groups: sedentary ZDF (Con-ZDF), exercised ZDF (Ex-ZDF), sedentary ZLC (Con-ZLC), and exercised ZLC (Ex-ZLC). Ex-ZDF and Ex-ZLC rats were trained (once every 3 days for 8 weeks) to climb a 1.1-m vertical (80° incline) ladder with weights secured to their tail for progressive workload resistance exercise (the training was started at 50% or 70% of maximal weight of the last trial). Body weight, grip strength and intraperitoneal glucose tolerance test (IPGTT) were evaluated at every week. Body composition was analyzed by PET-CT (Positron Emission Tomography – Computed Tomography) and expression of IL-15 was measured using ELISA in extracted soleus muscle and tibialis anterior muscle. Results: After 8 weeks of resistance training, substantial reduction of the body weight was observed in Ex-ZDF compared to Con-ZDF. Grip strength was also significantly increased in Ex-ZDF compared to Con-ZDF after 8 weeks of regular strength exercise indicating the efficacy of resistance training. Glucose tolerance (IPGTT) was significantly improved in Ex-ZDF (p<0.05) compared to Con-ZDF showing more delayed drop in blood glucose level between 90 min and 120 min. Concurrently, the expression of IL-15 was significantly increased (p<0.01) after training especially in soleus muscle of Ex-ZDF compared to Con-ZDF and also there was a tendency of increase in IL-15 expression in tibialis anterior muscle in Ex-ZDF as well. Accordingly, PET-CT scan showed that muscle quality tended to be higher in Ex-ZDF than Con-ZDF while no significant difference between Con-ZLC and Ex-ZLC. Discussion: 8 weeks of progressive resistance exercise significantly improved glucose tolerance with the concomitant increase of IL-15 expression in hind-limb muscles suggesting that increased level of IL-15 in skeletal muscle by resistance exercise might be a potential mediator in glucose regulation of type 2 diabetes. Further study is needed to elucidate the mechanisms by which how increased IL-15 expression in skeletal muscle by resistance exercise exerts a favorable influence on impaired glucose metabolism in type 2 diabetes mellitus.

Progressive Resistance Training and Cancer Testis (PROTRACT) - Efficacy of resistance training on muscle function, morphology and inflammatory profile in testicular cancer patients undergoing chemotherapy: design of a randomized controlled trial

BackgroundStandard treatment for patients with disseminated germ cell tumors is combination chemotherapy with bleomycin, etoposide and cisplatin (BEP). This treatment is highly effective, but the majority of patients experience severe adverse effects during treatment and are at risk of developing considerable long-term morbidity, including second malignant neoplasms, cardiovascular disease, and pulmonary toxicity. One neglected side effect is the significant muscular fatigue mentioned by many patients with testicular cancer both during and after treatment. Very limited information exists concerning the patho-physiological effects of antineoplastic agents on skeletal muscle. The primary aim of this study is to investigate the effects of BEP-treatment on the skeletal musculature in testicular cancer patients, and to examine whether the expected treatment-induced muscular deterioration can be attenuated or even reversed by high intensity progressive resistance training (HIPRT).Design/MethodsThe PROTRACT study is a randomized controlled trial in 30 testicular cancer patients undergoing three cycles of BEP chemotherapy. Participants will be randomized to either a 9-week HIPRT program (STR) initiated at the onset of treatment, or to standard care (UNT). 15 healthy matched control subjects (CON) will complete the same HIPRT program. All participants will take part in 3 assessment rounds (baseline, 9 wks, 21 wks) including muscle biopsies, maximum muscle strength tests, whole body DXA scan and blood samples. Primary outcome: mean fiber area and fiber type composition measured by histochemical analyses, satellite cells and levels of protein and mRNA expression of intracellular mediators of protein turnover. Secondary outcomes: maximum muscle strength and muscle power measured by maximum voluntary contraction and leg-extensor-power tests, body composition assessed by DXA scan, and systemic inflammation analyzed by circulating inflammatory markers, lipid and glucose metabolism in blood samples. Health related Quality of Life (QoL) will be assessed by validated questionnaires (EORTC QLQ-C30, SF-36).DiscussionThis study investigates the muscular effects of antineoplastic agents in testicular cancer patients, and furthermore evaluates whether HIPRT has a positive influence on side effects related to chemotherapy. A more extensive knowledge of the interaction between cytotoxic-induced physiological impairment and exercise-induced improvement is imperative for the future development of optimal rehabilitation programs for cancer patients.Trial RegistrationCurrent Controlled Trials ISRCTN32132990.

Optimizing Exercise Outcomes: The Efficacy of Resistance Training Using Conventional vs. Novel Movement Arcs

The purpose of this study was to examine the effect of using multidirectional movement arcs in a resistance training program for the shoulder. It was hypothesized that multidirectional exercises performed against resistance would result in a greater positive adaptation of the muscle tissue than conventional movement patterns commonly used in strength training. Fourteen female athletes were initially assessed using a 1x repetition maximum (1xRM) test for shoulder flexion and shoulder abduction (dominant and nondominant arm). After randomization into 2 groups, subjects engaged in different strength training programs against Thera-Band resistance for 6 weeks. Follow-up testing was then completed. Group A was assigned a strength training program that used conventional curvilinear movement arcs. Group B completed resistance training that comprised multidirectional exercises. Both the conventional and novel strength training programs induced improvements in the 1x RM test (p < 0.01). There was a trend toward greater improvements in the nonconventional training group, but this was statistically insignificant. This suggests that varying the axial or torsional loading of muscle fibers during strength training may confer further benefit to conventional methods of training variation. Consequently, further studies are indicated to investigate if resistance training that incorporates multidirectional movement arcs is more effective than those used in conventional strength training programs. This may have implications on the design of future training programs that aim to optimize strength gains.

Resistance training and timed essential amino acids protect against the loss of muscle mass and strength during 28 days of bed rest and energy deficit

Spaceflight and bed rest (BR) result in losses of muscle mass and strength. Resistance training (RT) and amino acid (AA) supplementation are potential countermeasures to minimize these losses. However, it is unknown if timing of supplementation with exercise can optimize benefits, particularly with energy deficit. We examined the effect of these countermeasures on body composition, strength, and insulin levels in 31 men (ages 31-55 yr) during BR (28 days) followed by active recovery (14 days). Subjects were randomly assigned to essential AA supplementation (AA group, n = 7); RT with AA given 3 h after training (RT group, n = 12); or RT with AA given 5 min before training (AART group, n = 12). Energy intake was reduced by 8 +/- 6%. Midthigh muscle area declined with BR for the AA > RT > AART groups: -11%, -3%, -4% (P = 0.05). Similarly, greatest losses in lower body muscle strength were seen in the AA group (-22%). These were attenuated in the exercising groups [RT (-8%) and AART (-6%; P < 0.05)]. Fat mass and midthigh intramuscular fat increased after BR in the AA group (+3% and +14%, respectively), and decreased in the RT (-5% and -4%) and AART groups (-1 and -5%; P = 0.05). Muscle mass and strength returned toward baseline after recovery, but the AA group showed the lowest regains. Combined resistance training with AA supplementation pre- or postexercise attenuated the losses in muscle mass and strength by approximately two-thirds compared with AA supplement alone during BR and energy deficit. These data support the efficacy of combined AA and RT as a countermeasure against muscle wasting due to low gravity.

Safety and Efficacy of Resistance Training in Patients With Chronic Heart Failure: Research‐Based Evidence

Although a rich body of research exists regarding the safety and efficacy of resistance training, health care providers continue to caution patients with heart failure not to engage in this type of exercise. Research studies utilizing resistance training demonstrate improvements in muscular strength and endurance, New York Heart Association functional class, and quality of life. Despite the hemodynamic changes which occur during resistance exercise, no negative outcomes have been reported. The purpose of this paper is to review the most current research regarding the use of resistance training with heart failure patients to provide assistance to clinicians and enable them to provide education and appropriate recommendations to their patients.