Lift weights to fight overweight

Unveiling the Effects of Interval Resistance Training and Chlorella Vulgaris Supplementation on Meteorin-like Protein and Oxidative Stress in Obese Men

Background

Dysregulation of adipocyte function occurs in obesity. Meteorin-like protein (Metrnl) is a newly discovered modulator of inflammation, metabolism, and differentiation of human adipocytes. The dietary supplement Chlorella Vulgaris (CV) reduces hyperlipidemia, hyperglycemia, and oxidative stress in clinical trials.

Objectives

To explore the impact of 12 wks of interval resistance training (IRT) and CV supplementation on plasma levels of Metrnl and oxidative stress in males with obesity.

Methods

Forty-four obese men (BMI: 32.0 ± 1.5 kg/m2, weight: 101.1 ± 2.2 kg, age: 23-35 years) were randomly assigned into 4 groups (n = 11/group): control (CON), CV supplement (CV), IRT, and CV + IRT (CVIRT). The IRT was performed for 12 wks (3 sessions per week). The treatment consisted of a daily intake of CV (1800 mg capsule) or placebo capsules. Blood samples were collected 48 hours before and after the interventions to analyze biomedical measurements.

Results

The IRT and CVIRT groups had elevations in plasma Metrnl, superoxide dismutase, and total antioxidant capacity levels (all P < 0.0001), and reductions in malondialdehyde (P < 0.0001). Supplementation with CV significantly reduced malondialdehyde (P < 0.001) and increased total antioxidant capacity (P < 0.0001) but failed to alter superoxide dismutase or Metrnl (P > 0.05).

Conclusions

Although IRT and its combination with CV hold promise for improving Metrnl levels and oxidative status in obesity, combining IRT and CV do not yield greater benefits than IRT alone. Although standalone CV supplementation could favorably impact certain markers of oxidative stress, the effectiveness of CV supplementation appears to have a relatively limited effect across assessed biomarkers and requires further investigation.

Does resistance training ameliorate cancer-related fatigue in cancer survivors? A systematic review with meta-analysis

PURPOSE

Cancer-related fatigue (CRF) is unrelenting. As neither rest nor sleep ameliorates cognitive, emotional, and physical symptoms, quality of life is diminished. This study examines resistance training (RT) effectiveness on CRF in cancer survivors. The secondary aims were to identify the dose-response relationship of RT frequency, intensity, and volume on CRF in different cancer survivor populations.

MATERIALS AND METHODS

Systematic searches via numerous databases for RCTs were performed in June 2022. Patient-reported outcome measures (PROM), were analysed, pre-to-post intervention, using a random-effects model. The Physiotherapy Evidence Database (PEDro) scale informed methodological quality assessment.

RESULTS

Eight studies were included (cancer survivors: breast (BCS) = 5; endometrial (ECS) = 1; prostate (PCS) = 2). Overall, RT interventions ≥ 6 weeks elicited large significant reductions in CRF for FACIT-F (SMD = 0.932, p = <0.001) and moderate significant reductions in CRF for PFS-R (SMD = -0.622, p = 0.004).

CONCLUSION

Main findings indicate that RT ameliorates CRF, especially in BCS; however, individualised approaches should be advocated. Supervised training elicited the greatest positive outcomes, thus should be a pivotal part of the cancer rehabilitation pathway. Future studies should be adequately powered, undertake discrete analyses of different cancer types, and investigate chronic RT effects.

Tirzepatide and exercise training in obesity

OBJECTIVES

The purpose of this study was to investigate the effects of 6 weeks of resistance training (RT) combined with aerobic training (AT) and Tirzepatide supplementation on lipid profiles, insulin resistance, anthropometric characteristics and physical fitness in prediabetic obese soldiers.

METHODS

61 obese men were randomly divided into six groups: Placebo; Tirzepatide 5 mg (T5); Tirzepatide 2.5 mg (T2.5); Hypertrophy, Strength, Power-Circuit Training+Placebo (Ex+P); Hypertrophy, Strength, Power-Circuit Training+Tirzepatide 5 mg (Ex+T5); Hypertrophy, Strength, Power-Circuit Training+Tirzepatide 2.5 mg (Ex+T2.5). All training groups performed aerobic training (AT) after resistance training. Subjects trained for six weeks, three sessions per week. Before and after the intervention period, the participants were evaluated for anthropometric measures, body composition [body weight, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and fat mass (FM)], cardiorespiratory fitness (VO2max), and muscle strength (chest press 1RM and leg press 1RM). Blood biochemistry evaluations included triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), insulin level and insulin resistance (HOMA-IR). To evaluate the differences between the groups, ANCOVA statistical method was used along with Bonferroni's post hoc test, and the significance level was P < 0.05.

RESULTS

Body weight, BMI, WC, FM, FBG, LDL-C, TC, TG and HOMA-IR were significantly decreased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo, T5 and T2.5 groups. WHR significantly decreased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo group. HDL-C, chest press and leg press significantly increased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo, T5 and T2.5 groups. VO2max significantly increased and insulin significantly decreased in Ex+P group compared to Placebo, T5 and T2.5 groups. FM, FBG and TG were significantly decreased in both the T2.5 and T5 groups compared to Placebo group. HOMA-IR, LDL-C and TC significantly decreased in the T5 group compared to Placebo group. Also, leg press significantly increased in Ex+P group compared to all other groups.

CONCLUSIONS

Performing six weeks of combined resistance and aerobic training in the form of RT+AT alone is more effective than the simultaneous use of Tirzepatide on cardiorespiratory fitness, strength, and modulating insulin levels. Taking Tirzepatide in doses of 5 mg and 2.5 mg in combination with exercise training did not have a significant advantage over exercise training alone. Finally, taking Tirzepatide in doses of 5 mg or 2.5 mg in combination with exercise training is not significantly superior to each other.

The non-modifiable factors age, gender, and genetics influence resistance exercise

Muscle mass and force are key for movement, life quality, and health. It is well established that resistance exercise is a potent anabolic stimulus increasing muscle mass and force. The response of a physiological system to resistance exercise is composed of non-modifiable (i.e., age, gender, genetics) and modifiable factors (i.e., exercise, nutrition, training status, etc.). Both factors are integrated by systemic responses (i.e., molecular signaling, genetic responses, protein metabolism, etc.), consequently resulting in functional and physiological adaptations. Herein, we discuss the influence of non-modifiable factors on resistance exercise: age, gender, and genetics. A solid understanding of the role of non-modifiable factors might help to adjust training regimes towards optimal muscle mass maintenance and health.

Effects of 6-Week Betaine Supplementation on Muscular Performance in Male Collegiate Athletes

The purpose of this study was to investigate the effects of 6-week betaine supplementation during a preparatory period of collegiate athletes on muscular power and strength. Sixteen male collegiate athletes received 5 g/day of betaine (betaine group, n = 9) or carboxymethyl cellulose (placebo group, n = 7) for 6 weeks. All participants engaged in their regular training during the experimental period. The overhead medicine-ball throw (OMBT), countermovement jump, and maximal strength (one repetition maximum, 1-RM) on the bench press, overhead press, half squat, and sumo dead lift by the participants were assessed before and after betaine supplementation. Blood lipids were also analyzed before and after betaine supplementation. After supplementation, there were no significant differences between betaine and placebo groups on any variables. Compared to presupplementation, the performance of OMBT and 1-RM of overhead press and half squat in the betaine group had significantly improved (p < 0.05). By contrast, no significant differences were observed in the placebo group before and after supplementation. Blood analysis revealed no negative effect on blood lipid profiles. Betaine seems to be a useful nutritional strategy to improve and maintain performance during 6-week preparatory periods in collegiate athletes.

Resistance Training before, during, and after COVID-19 Infection: What Have We Learned So Far?

At the end of 2019, a severe acute respiratory syndrome caused by SARS-CoV-2 started a pandemic, leading to millions of deaths and many important political and social changes. Even in the absence of contamination, the mobility reduction, social distancing and closing of exercise facilities negatively affected physical activity and conditioning, which is associated with muscle atrophy, loss of muscle strength, and reductions in functional capacity. In cases of infection, it has been shown that increased physical capacity is associated with decreased hospitalization and mortality risk. Although millions of people have died from COVID-19, most contaminated individuals survived the infection, but carried different sequelae, such as the severe loss of physical function and a reduced quality of life. Among different physical exercise models that might help to prevent and treat COVID-19-related conditions, resistance training (RT) might be particularly relevant. Among its benefits, RT can be adapted to be performed in many different situations, even with limited space and equipment, and is easily adapted to an individual's characteristics and health status. The current narrative review aims to provide insights into how RT can be used in different scenarios to counteract the negative effects of COVID-19. By doing this, the authors expect to provide insights to help deal with the current pandemic and similar events the world may face in the future.

Adapted physical activity in subjects and athletes recovering from covid-19: a position statement of the Società Italiana Scienze Motorie e Sportive

Coronavirus disease 2019 (COVID-19) is a worldwide pandemic illness that is impacting the cardiovascular, pulmonary, musculoskeletal, and cognitive function of a large spectrum of the worldwide population. The available pharmacological countermeasures of these long-term effects of COVID-19 are minimal, while myriads of non-specific non-pharmacological treatments are emerging in the literature. In this complicated scenario, particular emphasis should be dedicated to specific exercise interventions tailored for subjects and athletes recovering from COVID-19. Specific guidelines on adapted physical activity in this critical population are unavailable so far, therefore, in this position statement of the Società Italiana di Scienze Motorie e Sportive (SISMeS) the members of the steering committee of the research group Attività Motoria Adattata, Alimentazione, Salute e Fitness have indicated the adapted physical activity approaches to counteract the long-term effects of the COVID-19, both in good health people and athletes.

May the Force and Mass Be With You-Evidence-Based Contribution of Mechano-Biological Descriptors of Resistance Exercise

Skeletal muscle is one of the most important tissues of the human body. It comprises up to 40% of the body mass and is crucial to survival. Hence, the maintenance of skeletal muscle mass and strength is pivotal. It is well-established that resistance exercise provides a potent anabolic stimulus to increase muscle mass and strength in men and women of all ages. Resistance exercise consists of mechano-biological descriptors, such as load, muscle action, number of repetitions, repetition duration, number of sets, rest interval between sets, frequency, volitional muscular failure, and range of motion, which can be manipulated. Herein, we discuss the evidence-based contribution of these mechano-biological descriptors to muscle mass and strength.

Effects of Functional Strength Training on Functional Movement and Balance in Middle-Aged Adults

Functional movement deficiencies cause falls and injuries in adults. Functional strength training (FST) is emerging as a new training method for athletes, middle-aged and older adults, to improve functional movement: The present study was conducted in order to investigate the effects of FST on balance and functional movement in healthy and independent middle-aged adults. The sample for this study consisted of 46 physically active individuals (24 female and 22 male). A total of 46 subjects were divided based on randomly into the functional strength training (FST) group (n = 26) aged: 51.55 ± 3.73 years; height: 168.69 ± 8.8 cm; body mass: 75.88 ± 12.18; and traditional strength training (TST) group (n = 20) age: 52.85 ± 4.01; height: 166.9 ± 9.98; body mass: 76.15 ± 10.45. Each group performed 24 sessions of a training protocol three-time a week. The functional movement was assessed using the functional movement screen (FMS) protocol. Balance performance was determined by using the balance error scoring system (BESS). Bodyweight and body fat ratio were measured using bioelectric impedance. There was a significant statistical difference between FMS total scores after an eight-week FST in the FST group. After the intervention, the functional strength group tended to have significantly better balance control than the traditional strength group (p = 0.01). Statistically, significant differences were observed between pre-test and post-test in the intervention group on BMI, body fat, and body mass (p = 0.01). There were not found significant differences in balance control and FMS score in TST group. As a result of this study, FST positively affected the FMS total score and balance performance in middle-aged adults. Early detections of the deficiencies in functional movement and balance in the middle ages may reduce the risk of insufficiency and fall in adults through targeted functional strength training intervention.

Physical activity, musculoskeletal disorders, sleep, depression, and quality of life before and after bariatric surgery

Objectives

This study aims to evaluate physical activity, sleep, depression, quality of life, and musculoskeletal problems pre- and postoperatively in morbidly obese patients who underwent bariatric surgery and analyze the factors that are strongly associated with physical activity.

Patients and methods

This prospective study conducted between January 2016 and May 2017 included 27 patients (4 males, 23 females; mean age 37.1±10.4 years; range, 18 to 52 years) who underwent bariatric surgery and 20 healthy controls (3 males, 17 females; mean age 32.0±5.7 years; range, 26 to 46 years). All patients were evaluated by using the short form of International Physical Activity Questionnaire (IPAQ), Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI), and short form 36 (SF-36). Patients were evaluated for regional musculoskeletal pain including back, waist, hip, knee, ankle, heel, and metatarsal pain using Visual Analog Scale. Presence of pes planus was recorded. The examinations and tests performed in the preoperative period were repeated at postoperative six months and the results were compared with the control group.

Results

The body mass index was 46.2±5.2 kg/m² preoperatively and 33.8±5.0 kg/m² postoperatively (p<0.001). The total IPAQ was 345.4±172.8 metabolic equivalent (MET)-min/week preoperatively and 672.8±227.8 MET-min/week postoperatively (p<0.001). Pittsburgh Sleep Quality Index was 7.6±3.0 preoperatively and 3.5±2.4 postoperatively, whereas BDI was 20.2±8.5 preoperatively and 9.9±7.4 postoperatively. The results were statistically significant (p<0.001, p<0.001, respectively). A statistically significant improvement was found in all subsections of the SF-36. Pre- and postoperative results of the 27 patients were compared with those of the control group.

Conclusion

Obesity is significantly associated with joint pain, physical function impairment, depression, and sleep disorders. Significant weight loss after bariatric surgery improves functional recovery and patient's psychology in a short time.

The "Journal of Functional Morphology and Kinesiology" Journal Club Series: Highlights on Recent Papers in Corrective Exercise

We are glad to introduce the Journal Club of Volume Five, fourth Issue. This edition is focused on relevant studies published in the last few years in the field of corrective exercise, chosen by our Editorial Board members and their colleagues. We hope to stimulate your curiosity in this field and to share a passion for sport with you, seen also from the scientific point of view. The Editorial Board members wish you an inspiring lecture.

Resistance Training Safety during and after the SARS-Cov-2 Outbreak: Practical Recommendations

In December of 2019, there was an outbreak of a severe acute respiratory syndrome caused by the coronavirus 2 (SARS-CoV-2 or COVID-19) in China. The virus rapidly spread into the whole world causing an unprecedented pandemic and forcing governments to impose a global quarantine, entering an extreme unknown situation. The organizational consequences of quarantine/isolation are absence of organized training and competition, lack of communication among athletes and coaches, inability to move freely, lack of adequate sunlight exposure, and inappropriate training conditions. The reduction of mobility imposed to contain the advance of the SARS-Cov-2 pandemic can negatively affect the physical condition and health of individuals leading to muscle atrophy, progressive loss of muscle strength, and reductions in neuromuscular and mechanical capacities. Resistance training (RT) might be an effective tool to counteract these adverse consequences. RT is considered an essential part of an exercise program due to its numerous health and athletic benefits. However, in the face of the SARS-Cov-2 outbreak, many people might be concerned with safety issues regarding its practice, especially in indoor exercise facilities, such as gyms and fitness centers. These concerns might be associated with RT impact in the immune system, respiratory changes, and contamination due to equipment sharing and agglomeration. In this current opinion article, we provide insights to address these issues to facilitate the return of RT practices under the new logistical and health challenges. We understand that RT can be adapted to allow its performance with measures adopted to control coronavirus outbreak such that the benefits would largely overcome the potential risks. The article provides some practical information to help on its implementation.

Effects of 6 Weeks of Traditional Resistance Training or High Intensity Interval Resistance Training on Body Composition, Aerobic Power and Strength in Healthy Young Subjects: A Randomized Parallel Trial

Consistent practice of physical activity has well known positive effects on general health; however, time for exercise remains one major barrier for many. An acute bout of high intensity interval resistance training (HIIRT) increases acute resting energy expenditure (REE) and decreases respiratory ratio (RR), suggesting its potential role on weight loss and increased fatty acid oxidation. The aim of this study was to test the long-term effect of HIIRT on body composition, lipid profile and muscle strength using a randomized parallel trial. Twenty healthy young adults (22.15 1.95 years) were randomized to perform either a HIIRT (N = 11) protocol, consisting of three sets of 6 repetitions at 6 repetition maximum (RM) and then 20 seconds of rest between repetitions until exhaustion repeated for 3 times with 2'30″ rest between sets or a traditional training (TRT, N = 9) protocol of 3 sets of 15 reps with 75 sec of rest between sets. Body composition, resting energy metabolism, aerobic capacity, muscle strength and blood measurements were taken before and after 8 weeks of training. Both protocols enhanced muscle strength, but only HIIRT improved endurance strength performance (+22.07%, p < 0.05) and lean body mass (+2.82%, p < 0.05). REE and RR were unaltered as lipid profile. HIIRT represents a valid training method to improve muscle strength and mass, but its role on body weight control was not confirmed.

Relationship between V̇o2peak, cycle economy, and mitochondrial respiration in untrained/trained

Aerobic capacity is negatively related to locomotion economy. The purpose of this paper is to determine what effect aerobic exercise training has on the relationship between net cycling oxygen uptake (inverse of economy) and aerobic capacity [peak oxygen uptake (V̇o_2peak)], as well as what role mitochondrial coupled and uncoupled respiration may play in whole body aerobic capacity and cycling economy. Cycling net oxygen uptake and V̇o_2peak were evaluated on 31 premenopausal women before exercise training (baseline) and after 8-16 wk of aerobic training. Muscle tissue was collected from 15 subjects at baseline and post-training. Mitochondrial respiration assays were performed using high-resolution respirometry. Pre- (r = 0.46, P < 0.01) and postexercise training (r = 0.62, P < 0.01) V̇o_2peak and cycling net oxygen uptake were related. In addition, uncoupled and coupled fat respiration were related both at baseline (r = 0.62, P < 0.01) and post-training (r = 0.89, P < 01). Post-training coupled (r = 0.74, P < 0.01) and uncoupled carbohydrate respiration (r = 0.52, P < 05) were related to cycle net oxygen uptake. In addition, correlations between V̇o_2peak and cycle net oxygen uptake persist both at baseline and after training, even after adjusting for submaximal cycle respiratory quotient (an index of fat oxidation). These results suggest that the negative relationship between locomotion economy and aerobic capacity is increased following exercise training. In addition, it is proposed that at least one of the primary factors influencing this relationship has its foundation within the mitochondria. Strong relationships between coupled and uncoupled respiration appear to be contributing factors for this relationship.NEW & NOTEWORTHY The negative relationship between cycle economy and aerobic capacity is increased following exercise training. The strong relationship between coupled and uncoupled respiration, especially after training, appears to be contributing to this negative relationship between aerobic capacity and cycling economy, suggesting that mitochondrial economy is not increased following aerobic exercise training. These results are suggestive that training programs designed to improve locomotion economy should focus on changing biomechanics.

Effects of Adding Single Joint Exercises to a Resistance Training Programme in Trained Women

BACKGROUND

The present study's aim was to compare the changes in muscle performance and anthropometric measures in trained women performing RT programs composed only of MJ exercises or programmes that involve the addition of SJ exercises.

METHODS

Seventeen trained women were randomised to MJ or MJ+SJ. Both groups performed the same MJ exercises following a nonlinear periodisation model for 8 weeks. The only difference was that the MJ+SJ group also performed SJ exercises. The participants were tested for 10 repetition maximum (10 RM), flexed arm circumference, and both biceps and triceps skinfold.

RESULTS

Both groups significantly increased 10 RM load for the bench press (12.6% MJ and 9.2% MJ+SJ), triceps (15.6% MJ and 17.9% MJ+SJ), pull down (9.8% MJ and 8.3% MJ+SJ), biceps (14.0% MJ and 13.0% MJ+SJ), leg press (15.2% MJ and 12.8% MJ+SJ) and knee extension (10.2% MJ and 9.1% MJ+SJ). The decreases in triceps (-5.1% MJ and -5.3% MJ+SJ) and biceps (-6.5% MJ and -5.7% MJ+SJ) skinfolds were also significant as were the increases in arm circumference (1.47% MJ and 1.58% MJ+SJ). In all tests there was nothing significantly different between groups.

CONCLUSIONS

The use of SJ exercises as a complement to a RT programme containing MJ exercises brings no additional benefit to trained women.

A Benefit of Being Heavier Is Being Strong: a Cross-Sectional Study in Young Adults

Background

In this study, the main hypothesis is that heavier people enjoy strength exercises more than normal-weight people, mediated by fat-free mass and muscle strength. Further, it is hypothesized that heavier people are better in strength exercises and enjoy strength exercises more compared to aerobic exercises.

Methods

In a cross-sectional study, height, weight, body composition (i.e., fat mass and fat-free mass by underwater weighing), muscle strength (i.e., one-repetition maximal strength for the leg press and chest press), maximal aerobic exertion (VO₂max) during cycle ergometry, and psychological determinants (i.e., attitudes, intentions, and self-determined motivations for strength exercises and aerobic exercises using questionnaires) were measured in 68 participants (18–30 years).

Results

Significant correlations between weight/BMI and fat-free mass (index) (r values = .70–.80, p values < .001), fat-free mass and muscle strength (r values = .35–.55, p values < .05), and muscle strength and attitudes, intentions, and motivation for strength exercises were found (r values = .29–.43, p values < .05); BMI was related to psychological determinants via fat-free mass and muscle strength. Furthermore, participants with a higher BMI are significantly better in strength exercises, more intrinsically motivated, and less motivated to do strength exercises compared to aerobic exercises (all p values < .05). Trends in the same direction were found for the following variables: instrumental attitude, experiential attitude, and intention (p values < .1).

Conclusions

Strength exercises could be more appropriate for heavier people and might therefore be a valuable component in physical activity programs for people who are overweight or obese.

Electronic supplementary material

The online version of this article (10.1186/s40798-018-0125-4) contains supplementary material, which is available to authorized users.

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.

Impact of a motivational resistance-training programme on adherence and body composition in the elderly

Lack of physical activity is one of the major causes for obesity and functional disability in the elderly. Including regular exercise in the elderly's lifestyle is not an easy task. The main objective was to analyse the effect of a motivational resistance-training programme on satisfying the individual's psychological needs, level of self-determination and body composition. A quasi-experimental study was performed with 47 volunteers (29 females, 18 males) of 67-75 years of age, divided into two groups: experimental (n = 27) and control (n = 20). A 12-week intervention programme was performed, with a total of 36 sessions. The results of the inter-group analysis indicated significant differences in the post-test measurement between the experimental group and the control group (in favour of the experimental group) regarding basic psychological needs. The experimental group, in comparison to the control group, significantly decreased their percentage of fat mass and increased muscle mass. Body weight and BMI values increased in the control group, while significantly decreasing in the experimental group. In conclusion, the motivational resistance-training programme in the elderly gave rise to positive significant changes at the physical, psychological and social levels, according to the definition of health by the World Health Organization.

Resistance Training with Single vs. Multi-joint Exercises at Equal Total Load Volume: Effects on Body Composition, Cardiorespiratory Fitness, and Muscle Strength

The present study aimed to compare the effects of equal-volume resistance training performed with single-joint (SJ) or multi-joint exercises (MJ) on VO₂max, muscle strength and body composition in physically active males. Thirty-six participants were divided in two groups: SJ group (n = 18, 182.1 ± 5.2, 80.03 ± 2.78 kg, 23.5 ± 2.7 years) exercised with only SJ exercises (e.g., dumbbell fly, knee extension, etc.) and MJ group (n = 18, 185.3 ± 3.6 cm, 80.69 ± 2.98 kg, 25.5 ± 3.8 years) with only MJ exercises (e.g., bench press, squat, etc.). The total work volume (repetitions × sets × load) was equated between groups. Training was performed three times a week for 8 weeks. Before and after the training period, participants were tested for VO₂max, body composition, 1 RM on the bench press, knee extension and squat. Analysis of covariance (ANCOVA) was used to compare post training values between groups, using baseline values as covariates. According to the results, both groups decreased body fat and increased fat free mass with no difference between them. Whilst both groups significantly increased cardiorespiratory fitness and maximal strength, the improvements in MJ group were higher than for SJ in VO₂max (5.1 and 12.5% for SJ and MJ), bench press 1 RM (8.1 and 10.9% for SJ and MJ), knee extension 1 RM (12.4 and 18.9% for SJ and MJ) and squat 1 RM (8.3 and 13.8% for SJ and MJ). In conclusion, when total work volume was equated, RT programs involving MJ exercises appear to be more efficient for improving muscle strength and maximal oxygen consumption than programs involving SJ exercises, but no differences were found for body composition.

Comparison of elbow flexor isokinetic peak torque and fatigue index between men and women of different training level

The purpose of the study was to compare elbow flexion peak torque (PT) and fatigue index (FI) during isokinetic concentric contractions in men and women with different training levels. Sixty-eight young men and women were divided into four groups: resistance trained men (RTM), non-resistance trained men (NRTM), resistance trained women (RTW) and non- resistance trained women (NRTW). Participants performed two tests on an isokinetic dynamometer, one to evaluate PT and one to evaluate FI. Significant interactions were found for sex and resistance training status with both PT and FI. In general, resistance-trained subjects had higher PT, and women showed lower PT than men. PT values were 67.12 ± 9.93 N·m for RTM, 49.9 ± 8.5 N·m for NRTM, 41.84 ± 7.52 N·m for RTW, and 26.05 ± 3.34 N·m for NRTW. Separate analysis revealed that RTM had higher PT than all other groups. However, FI was higher for NRTM than for RTM and NRTW and no difference was found between RTM and NRTW. FI was 37.86 ± 10.89 % for RTW, 45.74 ± 13.17 % for NTRW, 45.89 ± 8.24 % for RTM, and 51.92 ± 4.5 % for NRTM. Women produce lower PT, and have a higher fatigue tolerance than men of similar training status. Considering that women showed to be more resistant to fatigue than men, women can manipulate training variables differently from men, such as, including more repetitions at the same relative load or using higher relative loads at the same number of repetitions.

Chronic Effects of Resistance Training in Breast Cancer Survivors

Objective. To analyse effects of resistance training (RT) in breast cancer survivors (BCS) and how protocols and acute variables were manipulated. Methods. Search was made at PubMed, Science Direct, and LILACS. All articles published between 2000 and 2016 were considered. Studies that met the following criteria were included: written in English, Spanish, or Portuguese; BCS who have undergone surgery, chemotherapy, and/or radiotherapy; additional RT only; analysis of muscle performance, body mass composition (BMC), psychosocial parameters, or blood biomarkers. Results. Ten studies were included. PEDro score ranged from 5 to 9. Rest interval and cadence were not reported. Two studies reported continuous training supervision. All reported improvements in muscle strength, most with low or moderate effect size (ES), but studies performed with high loads presented large ES. Five described no increased risk or exacerbation of lymphedema. Most studies that analysed BMC showed no relevant changes. Conclusions. RT has been shown to be safe for BCS, with no increased risk of lymphedema. The findings indicated that RT is efficient in increasing muscle strength; however, only one study observed significant changes in BMC. An exercise program should therefore consider the manipulation of acute and chronic variables of RT to obtain optimal results.

Does exercise training affect resting metabolic rate in adolescents with obesity?

We evaluated the hypothesis that resistance exercise training performed alone or in combination with aerobic exercise training would increase resting metabolic rate (RMR) relative to aerobic-only and nonexercising control groups. Postpubertal adolescents (N = 304) aged 14-18 years with obesity (body mass index (BMI) ≥ 95th percentile) or overweight (BMI ≥ 85th percentile + additional diabetes risk factor(s)) were randomized to 4 groups for 22 weeks: Aerobic exercise training, Resistance exercise training, Combined aerobic and resistance exercise training, or Control. All participants received dietary counselling targeting a daily energy deficit of 250 kcal. RMR was measured by indirect calorimetry and body composition by magnetic resonance imaging. There was no significant change in RMR in any group, in spite of significant within-group increases in fat-free mass in the Aerobic, Resistance, and Combined exercise training groups. RMR at baseline and 6 months were Aerobic: 1972 ± 38 and 1990 ± 41; Resistance: 2024 ± 37 and 1992 ± 41; Combined: 2023 ± 38 and 1995 ± 38; Control: 2075 ± 38 and 2073 ± 39 kcal/day (p > 0.05). There were no between-group differences in RMR after adjustment for total body weight or fat-free mass between groups over time. Per-protocol analyses including only participants with ≥70% adherence, and analyses stratified by sex, also showed no within- or between-group differences in RMR. In conclusion, despite an increase in fat-free mass in all exercise groups, 6 months of aerobic, resistance, or combined training with modest dietary restriction did not increase RMR compared with diet only in adolescents with obesity.

The Dutch 'Focus on Strength' intervention study protocol: programme design and production, implementation and evaluation plan

BACKGROUND

Overweight youngsters are better in absolute strength exercises than their normal-weight counterparts; a physiological phenomenon with promising psychological impact. In this paper we describe the study protocol of the Dutch, school-based program 'Focus on Strength' that aims to improve body composition of 11-13 year old students, and with that to ultimately improve their quality of life.

METHODS

The development of this intervention is based on the Intervention Mapping (IM) protocol, which starts from a needs assessment, uses theory and empirical research to develop a detailed intervention plan, and anticipates program implementation and evaluation. This novel intervention targets first year students in preparatory secondary vocational education (11-13 years of age). Teachers are the program implementers. One part of the intervention involves a 30 % increase of strength exercises in the physical education lessons. The other part is based on Motivational Interviewing, promoting autonomous motivation of students to become more physically active outside school. Performance and change objectives are described for both teachers and students. The effectiveness of the intervention will be tested in a Randomized Controlled Trial in 9 Dutch high schools.

DISCUSSION

Intervention Mapping is a useful framework for program planning a school-based program to improve body composition and motivation to exercise in 11-13 year old adolescents by a "Focus on Strength".

TRIAL REGISTRATION

NTR5676 , registered 8 February 2016 (retrospectively registered).

Combating adolescent obesity: an integrated physiological and psychological perspective

PURPOSE OF REVIEW

Optimizing the approach to combat childhood obesity, we emphasize the importance of combining both biological and psychological knowledge. In such an approach, strength exercises might be an important aspect in the treatment and prevention of childhood obesity.

RECENT FINDINGS

Recent evidence indicates plausible effects of the role of resistance exercise in combating the negative health effects of childhood obesity. When looking at body composition, overweight youngsters do not only have a higher fat mass, but also a higher muscle mass compared with their normal-weight counterparts. With that, they are also stronger and better in exercises wherein the focus is on absolute strength, making them - under the right circumstances - more motivated to engage in resistance exercise and ultimately maintain a physically active lifestyle.

SUMMARY

More and more children are obese, and obese children become obese adults. One reason that overweight youngsters are not physically active is that they are outperformed by normal-weight youngsters, and one reason they are overweight is because they are not physically active. To combat childhood obesity, strength exercise might be a solution to break the vicious cycle.