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Background: The effects of combining resistance training (RT) and concurrent training (CT; resistance + endurance training) with varied protein doses on bone measures remain poorly understood. Hence, we conducted a comparison of the impacts of two high-protein diets (1.6 or 3.2 g kg−1 d−1) over 16 weeks in resistance-trained males, either with CT or RT alone. Methods: A total of forty-eight males, all of whom were resistance-trained, had the following demographics: 26.6 ± 6 years, body mass index: 25.6 ± 2.9 kg m−2 administered either 3.2 g kg−1 d−1 protein (CT2; n = 12; RT2; n = 12) or 1.6 g kg−1 d−1 protein (CT1; n = 12; RT1; n = 12) during 16 weeks (four sessions·w−1). Bone parameters were assessed pre- and post-intervention. Results: There was no significant interaction between the intervention group and time for the legs, arms, ribs, or pelvis area BMC and BMD (p > 0.05). For the BMD of the pelvis and the BMC of the right ribs, however, there were significant time effects noted (p < 0.05). Furthermore, there was a significant interaction between the intervention group and time in the lumbar and thoracic spines, with a particular time effect noted for the thoracic spine region (p < 0.05). The regional differences in skeletal responses to the intervention are highlighted by these data. Conclusion: Our findings show that the intake of two high-protein diets combined with RT and CT during 16 weeks had no adverse effects on bone tissue parameters. While these findings indicate that protein intake between 2 and 3 times the current RDI does not promote bone demineralization when consumed in conjunction with exercise, future studies investigating the long-term effects of chronic high protein intake on bone tissue health are warranted. [ABSTRACT FROM AUTHOR]

Dyslipidemia is a major risk factor for atherosclerosis. Identification of dyslipidemia in athletes has raised interest in establishing preventive strategies and reducing cardiovascular (CV) events. Nowadays, targets or "scores" for athletes are undefined. The aim of our study was to create a "Lipid Athlete Score" based on lipid parameters and derive score indexes to identify high-risk athletes. We retrospectively enrolled 957 Olympic athletes practicing different sporting disciplines (power, skills, endurance, and mixed), analyzing their CV profiles and anthropometrics; 55.4% were male, the mean age was 27.1 ± 5 years, and the mean body mass index (BMI) was 23.1 ± 3.2 kg/m2. Three hundred and forty-three athletes (35.8%) were dyslipidemic (LDL ≥ 115 mg/dL or LDL/HDL ≥ 1.90). Multivariate analysis revealed the following: male p = 0.001, OR 1.88 [0.41–2.51], familiarity for dyslipidemia p = 0.001, OR 2.82 [1.72–4.59], BMI ≥ 30 kg/m2 p = 0.001, OR 2.53 [1.46–4.38], and fat mass p = 0.001, OR 2.29 [1.38–3.80] were significant. Endurance athletes presented the lowest CV risk. We proposed a lipid athlete score including major (LDL ≥ 115 mg/dL and LDL/HDL ≥ 1.90) and minor criteria (male, BMI > 30 kg/m2 or fat mass >22% for males and 32% for females, familiarity for dyslipidemia, and conventional CV risk factors). Twelve athletes (1.2%) were at high risk, 150 athletes (15.7%) at medium risk, 171 athletes (17.9%) at low risk, and 624 (65.2%) were at no risk. Dyslipidemia is very common in elite athletes. We have defined a specific lipid athlete score based on lipid parameters and derived score indexes for the stratification of risk. In accordance with this tool, a substantial proportion of athletes (16.9%) were at medium-to-high risk and need early preventive strategies to improve their lipid profiles and reduce the future development of atherosclerotic CV diseases. [ABSTRACT FROM AUTHOR]

Purpose It is unclear whether resistance (RT) and concurrent training (CT; resistance plus endurance training) combined with different protein intakes have differential effects on muscle hypertrophy, strength, and performance. Therefore, we compared the effects of two high-protein diets (1.6 or 3.2 g.kg−1.d−1) during 16 weeks of either CT or RT alone in resistance-trained males. Methods Forty-eight resistance-trained males (age: 26 ± 6 yr, body mass index: 25.6 ± 2.9 kg.m−2) performed 16 weeks (four sessions·w−1) of CT or RT with either 1.6 g.kg−1.d−1 protein (CT1; n = 12; RT1; n = 12) or 3.2 g.kg−1.d−1 protein (CT2; n = 12; RT2; n = 12). Training adaptations were assessed pre-, mid-, and post-intervention. Results All measures of performance (endurance, vertical jump, and pull-up), lean mass, muscle strength, and power significantly increased post-intervention in all groups, but peak power gains were greater in RT2 compared with RT1 and CT1 (p .05). Conclusions With the exception of peak power, intake of 1.6 g.kg−1.d−1 of protein appears sufficient to maximize gains in lean mass, muscle strength, performance, and aerobic capacity during both RT and CT without influencing markers of kidney and liver function, indicating this daily protein amount is effective and safely tolerated in young, healthy adults.

Objectives: The purpose of this meta-analysis was to investigate the association of aerobic, resistance and concurrent exercises vs. control group on inflammaging markers [tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-1-beta, IL-8, and high sensitivity C-reactive protein (hs-CRP)] in overweight or obesity patients with heart failure (HF). Methods: The databases of Scopus, PubMed, Web of Science and Google Scholar were searched until August 31, 2022 for exercise interventions vs. control group on circulating inflammaging markers in patients with HF. Only randomized controlled trial (RCT) articles were included. Standardized mean difference (SMD) and 95% confidence intervals (95%CIs) were calculated (registration code = CRD42022347164). Results: Forty-six full-text articles (57 intervention arms and 3693 participants) were included. A significant reduction was occurred in inflammaging markers of IL-6 [SMD-0.205(95% CI:-0.332 to −0.078),p = 0.002] and hs-CRP [SMD −0.379 (95% CI:-0.556 to −0.202), p = 0.001] with exercise training in patients with HF. Analysis of subgroup by age, body mass index (BMI), type, intensity, duration of exercise and mean left ventricular ejection fraction (LVEF) revealed that there was a significant reduction in TNF-α for middle-aged (p = 0.031), concurrent training (p = 0.033), high intensity (p = 0.005), and heart failure with reduced ejection fraction (HFrEF) (p = 0.007) compared to the control group. There was a significant reduction in IL-6 for middle-aged (p = 0.006), overweight (p = 0.001), aerobic exercise (p = 0.001), both high and moderate intensities (p = 0.037 and p = 0.034), short-term follow-up (p = 0.001), and heart failure with preserved ejection fraction (HFpEF) (p = 0.001) compared to the control group. There was a significant reduction in hs-CRP for middle-aged (p = 0.004), elderly-aged (p = 0.001), overweight (p = 0.001), aerobic exercise (p = 0.001), concurrent training (p = 0.031), both high and moderate intensities (p = 0.017 and p = 0.001), short-term (p = 0.011), long-term (p = 0.049), and very long-term (p = 0.016) follow-ups, HFrEF (p = 0.003) and heart failure with mildly reduced ejection fraction (HFmrEF) (p = 0.048) compared to the control group. Conclusions: The results confirmed that aerobic exercise and concurrent training interventions were effective to improve inflammaging markers of TNF-α, IL-6, and hs-CRP. These exercise-related anti-inflammaging responses were observed across ages (middle-aged and elderly-aged), exercise intensities, duration of follow-ups, and mean LVEFs (HFrEF, HFmrEF and HFpEF) in overweight patients with HF.

Background: The effects of combining resistance training (RT) and concurrent training (CT; resistance + endurance training) with varied protein doses on bone measures remain poorly understood. Hence, we conducted a comparison of the impacts of two high-protein diets (1.6 or 3.2 g kg−1 d−1) over 16 weeks in resistance-trained males, either with CT or RT alone. Methods: A total of forty-eight males, all of whom were resistance-trained, had the following demographics: 26.6 ± 6 years, body mass index: 25.6 ± 2.9 kg m−2 administered either 3.2 g kg−1 d−1 protein (CT2; n = 12; RT2; n = 12) or 1.6 g kg−1 d−1 protein (CT1; n = 12; RT1; n = 12) during 16 weeks (four sessions·w−1). Bone parameters were assessed pre- and post-intervention. Results: There was no significant interaction between the intervention group and time for the legs, arms, ribs, or pelvis area BMC and BMD (p > 0.05). For the BMD of the pelvis and the BMC of the right ribs, however, there were significant time effects noted (p < 0.05). Furthermore, there was a significant interaction between the intervention group and time in the lumbar and thoracic spines, with a particular time effect noted for the thoracic spine region (p < 0.05). The regional differences in skeletal responses to the intervention are highlighted by these data. Conclusion: Our findings show that the intake of two high-protein diets combined with RT and CT during 16 weeks had no adverse effects on bone tissue parameters. While these findings indicate that protein intake between 2 and 3 times the current RDI does not promote bone demineralization when consumed in conjunction with exercise, future studies investigating the long-term effects of chronic high protein intake on bone tissue health are warranted.

The purpose of this study was to examine and compare the training and detraining effects of outdoor serial and integrated combined exercise programs on health, functional capacity, and physical fitness indices. Fifty-one untrained overweight/obese males (47 ± 4 years) were divided into a serial combined (SCG), an integrated combined (ICG), or a control (CG) group. The SCG and ICG implemented a 3-month training (3 sessions/week) consisting of walking and body weight exercises. The only difference between SCG and ICG was the sequence of aerobic and strength training. In SCG, the strength training was performed before aerobic training, while in ICG the aerobic and the strength training were alternated repeatedly in a predetermined order. Health, functional capacity, and physical fitness indices were measured before the training, following the termination of programs, and 1-month after training cessation. Following the training, both the SCG and ICG groups showed reduced blood pressure, heart rate, body fat, and waist-to-hip ratio (3–11%; p < 0.001), with improved respiratory function, muscle strength, aerobic capacity, flexibility, and balance (14–61%; p < 0.001). After 1-month of training cessation, significant reductions (p < 0.05) were observed in health indices and physical fitness without returning to baseline levels. However, there were no differences between SCG and ICG after training and training cessation (p > 0.05). In CG, all the above variables did not change. Furthermore, a great percentage of participants in both exercise groups (90%) reported high levels of enjoyment. In conclusion, both serial and integrated outdoor combined walking and body weight strength training programs are enjoyable and equally effective for improving health, functional capacity, and physical fitness indices in overweight/obese middle-aged males. [ABSTRACT FROM AUTHOR]

This review analyzes relevant variables involved in acute interference effects of concurrent training (CT) sessions of aerobic exercise followed by strength exercises. The aerobic exercise intensity, mode, volume, duration of recovery interval between exercises, muscle groups involved, and utilization of ergogenic aids are the variables identified in this review. High-intensity interval aerobic exercises result in more pronounced negative effects on strength-endurance exercise but not in maximal strength. Cycling results in more negative effects on strength-endurance performance exercise than running. A 4-hour to 8-hour recovery interval seems to be enough to avoid interference on strength-endurance performance. Reduction in strength-endurance performance is located in muscle groups involved in both exercises. Low aerobic exercise volume (3 km) with ∼18 minutes of duration does not diminish strength endurance, whereas higher volumes (5 and 7 km) with ∼30 and ∼42 minutes of duration, respectively, generate impairments. Caffeine, carbohydrate, and beta-alanine are not able to revert the deleterious effect on strength-endurance performance, whereas creatine and capsaicin analog supplementation are. Thus, these variables must be taken into consideration to prescribe and organize a CT session. This information may help coaches to organize exercise sessions that minimize or avoid the impairment in strength performance after aerobic exercises. [ABSTRACT FROM AUTHOR]

Aerobic exercise (AE) and strength exercise (SE) are reported to induce discrete and specific appetite-related responses; however, the effect of combining AE and SE (i.e., combined exercise; CE) remains relatively unknown. Twelve inactive overweight men (age: 48 ± 5 y; BMI: 29.9 ± 1.9 kg⋅m²) completed four conditions in a random order: 1) nonexercise control (CON) (50 min seated rest); 2) AE (50 min cycling; 75% VO2peak); 3) SE (10 x 8 leg extensions; 75% 1RM); and 4) CE (50% SE + 50% AE). Perceived appetite, and appetite-related peptides and metabolites were assessed before and up to 2 h postcondition (0P, 30P, 60P, 90P, 120P). Perceived appetite did not differ between trials (p < .05). Acylated ghrelin was lower at 0P in AE compared with CON (p = .039), while pancreatic polypeptide (PP) was elevated following AE compared with CON and CE. Glucose-dependent insulinotropic peptide (GIPtotal) was greater following all exercise conditions compared with CON, as was glucagon, although concentrations were generally highest in AE (p < .05). Glucose was acutely increased with SE and AE (p < .05), while insulin and C-peptide were higher after SE compared with all other conditions (p < .05). In inactive, middle-aged men AE, SE and CE each have their own distinct effects on circulating appetite-related peptides and metabolites. Despite these differential exercise-induced hormone responses, exercise mode appears to have little effect on perceived appetite compared with a resting control in this population. [ABSTRACT FROM AUTHOR]

Problem Statement: Although combined exercise (CE) is frequently prescribed for glycemic control of Type 2 Diabetes Mellitus (T2DM) subjects, beginning CE session with aerobic or resistance exercises can lead to distinct responses in capillary glucose, especially when training prescriptions differ in intensity and volume. Approach: This study aimed to evaluate the effect of exercise intensity, volume, and order within combined exercise sessions on glycemic response. Purpose: Forty T2DM subjects participated in this study. The subjects were divided into three different protocols: standard (S-P, n = 13), high intensity (HI-P, n = 16), and high volume (HV-P, n = 11) in two counter-balanced orders each [i.e., resistance exercise followed by aerobic exercise (R-A) or vice versa (A-R)]. The capillary glucose was evaluated before and after each CE session. Results: All protocols of combined exercise reduced glucose concentrations (p < .001). HV-P induced a glycemic reduction that was 2-fold higher than that observed in HI-P (34% vs. 18%; p < .05). Both exercise orders within combined exercise session reduced glucose concentrations (S-P: 25%, 28%; HI-P: 17%, 19%, and HV-P: 31%, 36% for A-R and R-A, respectively); however, R-A induced slightly larger (Cohen's d was 13-33% higher in R-A compared to A-R), but clinically relevant, reductions in all combined exercise protocols. Preexercise glucose concentrations were correlated to exercise-induced glucose reduction only in the A-R order (r = 65 to .79, p < .05). Conclusion: All combined exercise protocols were effective in decreasing glucose concentrations. Nonetheless, a higher magnitude of glucose-lowering effect occurred when a higher exercise volume was performed and when performing resistance instead of aerobic exercise in the first place. [ABSTRACT FROM AUTHOR]

Background and Objectives: The purpose of this study was to investigate the effects of a 12-week concurrent training (CT) (i.e., aerobic plus resistance exercise) on short–term blood pressure variability (BPV) and BP values in hypertensive patients with non-dippper BP nocturnal pattern and underlying coronary artery disease. Material and Methods: The study included 72 consecutive patients who were divided into two groups according to the nocturnal BP pattern: dipping pattern (33 pts) and non-dipping (39 pts). Before starting CT and at 12 weeks, patients underwent the six minute walk test, ergometric test, assessment of 1-repetiton maximum (1 RM), and 24/h BP monitoring (24-h ABPM). Results: After CT, exercise capacity increased in both groups in a similar fashion. Twenty-four/h systolic BPV and daytime systolic BPV decreased significantly in the dipping group while they were unchanged in the non-dipping group (between groups changes: −1.0 ± 0.4 mmHg and −1.3 ± 0.9 mmHg; p = 0.02 and p = 0.006, respectively). Twenty-four/h systolic BP and daytime systolic BP decreased significantly in the dipping group while they were unchanged in the non-dipping group (between groups changes: −7.1 ± 2.6 mmHg and −7.8 ± 2.4 mmHg; p = 0.004 and p = 0.002, respectively). Nighttime systolic BP and BPV was unchanged in both groups. Twenty-four/h diastolic BP presented small but not significant changes in both groups. Conclusions: The effects of CT on BPV and BP were blunted in hypertensive subjects with a non-dipping BP pattern.

The purpose of this study was to examine and compare the training and detraining effects of outdoor serial and integrated combined exercise programs on health, functional capacity, and physical fitness indices. Fifty-one untrained overweight/obese males (47 ± 4 years) were divided into a serial combined (SCG), an integrated combined (ICG), or a control (CG) group. The SCG and ICG implemented a 3-month training (3 sessions/week) consisting of walking and body weight exercises. The only difference between SCG and ICG was the sequence of aerobic and strength training. In SCG, the strength training was performed before aerobic training, while in ICG the aerobic and the strength training were alternated repeatedly in a predetermined order. Health, functional capacity, and physical fitness indices were measured before the training, following the termination of programs, and 1-month after training cessation. Following the training, both the SCG and ICG groups showed reduced blood pressure, heart rate, body fat, and waist-to-hip ratio (3–11%; p < 0.001), with improved respiratory function, muscle strength, aerobic capacity, flexibility, and balance (14–61%; p < 0.001). After 1-month of training cessation, significant reductions (p < 0.05) were observed in health indices and physical fitness without returning to baseline levels. However, there were no differences between SCG and ICG after training and training cessation (p > 0.05). In CG, all the above variables did not change. Furthermore, a great percentage of participants in both exercise groups (90%) reported high levels of enjoyment. In conclusion, both serial and integrated outdoor combined walking and body weight strength training programs are enjoyable and equally effective for improving health, functional capacity, and physical fitness indices in overweight/obese middle-aged males.

Concurrent exercise training has been suggested to create an ‘interference effect,’ attenuating resistance training-based skeletal muscle adaptations, including myofibre hypertrophy. Satellite cells support myofibre hypertrophy and are influenced by exercise mode. To determine whether satellite cells contribute to the ‘interference effect’ changes in satellite cell and myonuclear content were assessed following a period of training in 32 recreationally active males (age: 25 ± 5 year; body mass index: 24 ± 3 kg⋅m–2; mean ± SD) who undertook 12-week of either isolated (3 d⋅w–1) resistance (RES; n = 10), endurance (END; n = 10), or alternate day (6 d⋅w–1) concurrent (CET, n = 12) training. Skeletal muscle biopsies were obtained pre-intervention and after 2, 8, and 12 weeks of training to determine fibre type-specific cross-sectional area (CSA), satellite cell content (Pax7+DAPI+), and myonuclei (DAPI+) using immunofluorescence microscopy. After 12 weeks, myofibre CSA increased in all training conditions in type II (P = 0.0149) and mixed fibres (P = 0.0102), with no difference between conditions. Satellite cell content remained unchanged after training in both type I and type II fibres. Significant correlations were observed between increases in fibre type-specific myonuclear content and CSA of Type I (r = 0.63, P < 0.0001), Type II (r = 0.69, P < 0.0001), and mixed fibres (r = 0.72, P < 0.0001). Resistance, endurance, and concurrent training induce similar myofibre hypertrophy in the absence of satellite cell and myonuclear pool expansion. These findings suggest that myonuclear accretion via satellite cell fusion is positively correlated with hypertrophy after 12 weeks of concurrent training, and that individuals with more myonuclear content displayed greater myofibre hypertrophy.

Concurrent exercise training has been suggested to create an 'interference effect,' attenuating resistance training-based skeletal muscle adaptations, including myofibre hypertrophy. Satellite cells support myofibre hypertrophy and are influenced by exercise mode. To determine whether satellite cells contribute to the 'interference effect' changes in satellite cell and myonuclear content were assessed following a period of training in 32 recreationally active males (age: 25 ± 5 year; body mass index: 24 ± 3 kg⋅m–2; mean ± SD) who undertook 12-week of either isolated (3 d⋅w–1) resistance (RES; n = 10), endurance (END; n = 10), or alternate day (6 d⋅w–1) concurrent (CET, n = 12) training. Skeletal muscle biopsies were obtained pre-intervention and after 2, 8, and 12 weeks of training to determine fibre type-specific cross-sectional area (CSA), satellite cell content (Pax7+DAPI+), and myonuclei (DAPI+) using immunofluorescence microscopy. After 12 weeks, myofibre CSA increased in all training conditions in type II (P = 0.0149) and mixed fibres (P = 0.0102), with no difference between conditions. Satellite cell content remained unchanged after training in both type I and type II fibres. Significant correlations were observed between increases in fibre type-specific myonuclear content and CSA of Type I (r = 0.63, P < 0.0001), Type II (r = 0.69, P < 0.0001), and mixed fibres (r = 0.72, P < 0.0001). Resistance, endurance, and concurrent training induce similar myofibre hypertrophy in the absence of satellite cell and myonuclear pool expansion. These findings suggest that myonuclear accretion via satellite cell fusion is positively correlated with hypertrophy after 12 weeks of concurrent training, and that individuals with more myonuclear content displayed greater myofibre hypertrophy. [ABSTRACT FROM AUTHOR]

Abstract Objective To emphasize the mechanism of concurrent exercise effect on lipid disorders in insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD). Materials and methods Twenty male ApoE knockout mice were randomly divided into two groups: HFD group (n = 10) fed a high fat diet, and HFDE group (n = 10) with high-fat diet intervention for 12 weeks and swimming exercise. Other ten healthy male C57BL/6 J mice were fed a normal diet, and included as control group. Retro-orbital blood samples were collected for biochemical analysis. Oil red O staining of liver tissues was performed to confirm the exercise effect. Western blotting was performed to evaluate the expressions of PPAR-γ, CPT-1, MCAD. Results The levels of TG, TC, LDL, FFA, FIN, FPG and Homa-IRI in the HFD group were significantly higher than ND group, while these were markedly decreased in the HFDE group compared with HFD group. The Oil Red O staining of liver samples further confirmed the exercise effect on the change of lipid deposition in the liver. Western blotting showed increased expressions of PPAR-γ, CPT-1, MCAD induced by high fat diet were significantly downregulated by exercise. Conclusion A concurrent 12-week exercise protocol alleviated the lipid metabolism disorders of IR and NAFLD, probably via PPAR-γ/CPT-1/MCAD signaling.

In the basic principles of CrossFit®, the goal is to improve fitness, related to the simultaneous development of strength and endurance. This is also the main idea of concurrent training, which has been researched since the 1980s. This article aimed to analyze the acute and chronic effects of CrossFit® and to assess the relevance of using the concurrent training methodology. The findings show that CrossFit® is an intense form of exercise that affects the function of the endocrine, immune, and central nervous systems. It also has potential in the development of strength and endurance parameters. These conclusions were compared with relevant concurrent training studies. Although the CrossFit® interventions (workouts of the day) have much in common with concurrent training, methodological recommendations can only be partially transferred. The approach for training and athlete development must be based on the originality of this sport. [ABSTRACT FROM AUTHOR]

Introduction: A family history of type 2 diabetes (FH+) is a major risk factor for the development of insulin resistance and type 2 diabetes. However, it remains unknown whether exercise-induced improvements in insulin sensitivity and metabolic flexibility are impacted by a FH+. Therefore, we investigated whether improvements in insulin sensitivity, metabolic flexibility, body composition, aerobic fitness and muscle strength are limited by a FH+ following eight weeks of combined exercise training compared to individuals without a family history of type 2 diabetes (FH–).Methods: Twenty (n = 10 FH–, n = 10 FH+) young, healthy, sedentary, normoglycemic, Mexican-American males (age: FH– 22.50 ± 0.81, FH+ 23.41 ± 0.86 years; BMI: FH– 27.91 ± 1.55, FH+ 26.64 ± 1.02 kg/m2) underwent eight weeks of combined aerobic and resistance exercise training three times/week (35 min aerobic followed by six full-body resistance exercises). Insulin sensitivity was assessed via hyperinsulinemic euglycemic clamps. Metabolic flexibility was assessed by the change in respiratory quotient from fasted to insulin-stimulated states. Body composition was determined using dual-energy x-ray absorptiometry. Aerobic fitness was determined by a graded exercise test, and upper- and lower-body strength were assessed via one-repetition maximum bench press and leg strength dynamometer, respectively.Results: Insulin sensitivity, metabolic flexibility, aerobic fitness and strength were not different between groups (p > 0.05). Eight weeks of combined aerobic and resistance exercise training improved insulin sensitivity (FH– p = 0.02, FH+ p = 0.002), increased fat free mass (FH– p = 0.006, FH+ p = 0.001), aerobic fitness (FH– p = 0.03, FH+ p = 0.002), and upper- (FH– p = 0.0001, FH+ p = 0.0001) and lower-body strength (FH– p = 0.0009, FH+ p = 0.0003), but did not change metabolic flexibility (p > 0.05) in both groups. Exercise-induced improvements in metabolic outcomes were similar between groups.Conclusions: Insulin sensitivity, metabolic flexibility, aerobic fitness and strength were not compromised by a FH+. Additionally, a FH+ is not a limiting factor for exercise-induced improvements in insulin sensitivity, aerobic fitness, body composition, and strength in normoglycemic young Mexican-American men.

Introduction: A family history of type 2 diabetes (FH+) is a major risk factor for the development of insulin resistance and type 2 diabetes. However, it remains unknown whether exercise-induced improvements in insulin sensitivity and metabolic flexibility are impacted by a FH+. Therefore, we investigated whether improvements in insulin sensitivity, metabolic flexibility, body composition, aerobic fitness and muscle strength are limited by a FH+ following eight weeks of combined exercise training compared to individuals without a family history of type 2 diabetes (FH–). Methods: Twenty (n = 10 FH–, n = 10 FH+) young, healthy, sedentary, normoglycemic, Mexican-American males (age: FH– 22.50 ± 0.81, FH+ 23.41 ± 0.86 years; BMI: FH– 27.91 ± 1.55, FH+ 26.64 ± 1.02 kg/m2) underwent eight weeks of combined aerobic and resistance exercise training three times/week (35 min aerobic followed by six full-body resistance exercises). Insulin sensitivity was assessed via hyperinsulinemic euglycemic clamps. Metabolic flexibility was assessed by the change in respiratory quotient from fasted to insulin-stimulated states. Body composition was determined using dual-energy x-ray absorptiometry. Aerobic fitness was determined by a graded exercise test, and upper- and lower-body strength were assessed via one-repetition maximum bench press and leg strength dynamometer, respectively. Results: Insulin sensitivity, metabolic flexibility, aerobic fitness and strength were not different between groups (p > 0.05). Eight weeks of combined aerobic and resistance exercise training improved insulin sensitivity (FH– p = 0.02, FH+ p = 0.002), increased fat free mass (FH– p = 0.006, FH+ p = 0.001), aerobic fitness (FH– p = 0.03, FH+ p = 0.002), and upper- (FH– p = 0.0001, FH+ p = 0.0001) and lower-body strength (FH– p = 0.0009, FH+ p = 0.0003), but did not change metabolic flexibility (p > 0.05) in both groups. Exercise-induced improvements in metabolic outcomes were similar between groups. Conclusions: Insulin sensitivity, metabolic flexibility, aerobic fitness and strength were not compromised by a FH+. Additionally, a FH+ is not a limiting factor for exercise-induced improvements in insulin sensitivity, aerobic fitness, body composition, and strength in normoglycemic young Mexican-American men. [ABSTRACT FROM AUTHOR]

The influence of muscle sympathetic nerve activity (MSNA) responses on local vascular conductance during exercise are not well established. Variations in exercise mode and active muscle mass can produce divergent MSNA responses. Therefore, we sought to examine the effects of small-versus large-muscle mass dynamic exercise on vascular conductance and MSNA responses in the inactive limb. Thirty-five participants completed two study visits in a randomized order. During visit 1, superficial femoral artery (SFA) blood flow (Doppler ultrasound) was assessed at rest and during steady-state rhythmic handgrip (RHG; 1:1 duty cycle, 40% maximal voluntary contraction), one-leg cycling (17 ± 3% peak power output), and concurrent exercise at the same intensities. During visit 2, MSNA (contralateral fibular nerve microneurography) was acquired successfully in 12/35 participants during the same exercise modes. SFA blood flow increased during RHG (P < 0.0001) and concurrent exercise (P = 0.03) but not cycling (P = 0.91). SFA vascular conductance was unchanged during RHG (P = 0.88) but reduced similarly during concurrent and cycling exercise (both P < 0.003). RHG increased MSNA burst frequency (P = 0.04) without altering burst amplitude (P = 0.69) or total MSNA (P = 0.26). In contrast, cycling and concurrent exercise had no effects on MSNA burst frequency (both P ± 0.10) but increased burst amplitude (both P ≤ 0.001) and total MSNA (both P < 0.007). Across all exercise modes, the changes in MSNA burst amplitude and SFA vascular conductance were correlated negatively (r=0.43, P = 0.02). In summary, the functional vascular consequences of alterations in sympathetic outflow to skeletal muscle are most closely associated with changes in MSNA burst amplitude, but not frequency, during low-intensity dynamic exercise. [ABSTRACT FROM AUTHOR]

The current study examined the effects of a preceding bout of aerobic exercise (AE) on subsequent molecular signaling to resistance exercise (RE) of the elbow extensors. Eleven men performed unilateral elbow-extensor AE (~45 min at 70% peak workload) followed by unilateral RE (4 × 7 maximal repetitions) for both arms. Thus, one arm performed AE+RE interspersed with 15 min recovery, whereas the other arm conducted RE alone. Muscle biopsies were taken from the triceps brachii of each arm immediately before (PRE) and 15 min (POST1) and 3 h (POST2) after RE. Molecular markers involved in translation initiation, protein breakdown, mechanosignaling, and ribosome biogenesis were analyzed. Peak power during RE was reduced by 24% (±19%) when preceded by AE (P < 0.05). Increases in PGC1a and MuRF1 expression were greater from PRE to POST2 in AE+RE compared with RE (18-vs. 3.5- and 4- vs. 2-fold, respectively, interaction, P < 0.05). Myostatin mRNA decreased in both arms (P < 0.05). Phosphorylation of AMPK (Thr172) increased (2.5-fold), and 4E-BP1 (Thr37/46) decreased (2.0-fold), after AE (interactions, P < 0.05). p70 S6K, yesassociated protein, and c-Jun NH2-terminal kinase phosphorylation were unaltered, whereas focal adhesion kinase decreased ~1.5-fold, and β1- integrin increased ~1.3- to 1.5-fold, (time effect, P < 0.05). Abundance of 45S pre-ribosomal (r)RNA (internally transcribed spacer, ITS) decreased (~30%) after AE (interaction, P < 0.05), whereas CMYC mRNA was greater in AE+RE compared with RE (12-fold, P < 0.05). POLR1B abundance increased after both AE+RE and RE. All together, our results suggest that a single bout of AE leads to an immediate decrease in signaling for translation initiation and ribosome biogenesis. Yet, this did not translate into altered RE-induced signaling during the 3-h postexercise recovery period. [ABSTRACT FROM AUTHOR]

Introduction: Menopause seems to be among the factors related to the development of prediabetes and central obesity. Conversely, physical activity may have a major role in reducing metabolic syndrome in women of postmenopausal age. Material and methods: Forty-eight postmenopausal active and sedentary women within the ages of 45-65 years were randomized to four groups: 1) high-intensity concurrent interval exercise (HCI; n = 15), 2) moderate-intensity continuous concurrent exercise (MCC; n = 14), 3) control daily active (CDA; n = 10), and 4) control sedentary (COS; n = 9). The subjects in the preceding training groups exercised three times per week for 50-65 min/session with high/moderate concurrent exercise for 10 weeks. The levels of serum irisin, insulin sensitivity, abdominal fat distribution (visceral and subcutaneous), and total abdominal fat were measured at baseline and post-test. Results: This study showed that the HCI group had a significantly increased serum irisin (p < 0.001), stimulated favorable alterations in insulin sensitivity status (p = 0.003), and significantly decreased subcutaneous, visceral and, total abdominal fat (p < 0.001). Also, the insulin sensitivity status was significantly increased (p = 0.01) and subcutaneous abdominal fat significantly decreased in the MCC group (p = 0.018). However, this study's results did not find a considerable correlation between insulin sensitivity, irisin level, weight loss and abdominal fat distribution. Conclusions: High-intensity concurrent exercise has a greater influence on improving most metabolic-related parameters than moderate-intensity concurrent exercise. [ABSTRACT FROM AUTHOR]

Background: Protein ingestion during recovery from resistance-type exercise increases postexercise muscle protein synthesis rates. Whey protein has been reported to have greater anabolic properties than soy protein, an effect which may be attributed to the higher leucine content of whey.Objective: The objective of this study was to compare postprandial myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis rates after ingestion of carbohydrate with whey, soy, or soy protein enriched with free leucine (to match the leucine content of whey) during recovery from a single bout of concurrent resistance- and endurance-type exercise in young healthy men.Methods: In a randomized, double-blind, parallel-group design, 36 healthy young recreationally active men (mean ± SEM age: 23 ± 0.4 y) received a primed continuous infusion of l-[ring-13C6]-phenylalanine and l-[ring-3,5-2H2]-tyrosine and ingested 45 g carbohydrate with 20 g protein from whey (WHEY), soy (SOY), or leucine-enriched soy (SOY + LEU) after concurrent resistance- and endurance-type exercise. Blood and muscle biopsies were collected over a 360 min postexercise recovery period to assess MyoPS and MitoPS rates, and associated signaling through the mammalian target of rapamycin complex 1 (mTORC1).Results: Postprandial peak plasma leucine concentrations were significantly higher in WHEY (mean ± SEM: 322 ± 10 μmol/L) and SOY + LEU (328 ± 14 μmol/L) compared with SOY (216 ± 6 μmol/L) (P < 0.05). Despite the apparent differences in plasma leucinemia, MyoPS (WHEY: 0.054 ± 0.002; SOY: 0.053 ± 0.004; SOY + LEU: 0.056 ± 0.004%·h-1; P = 0.83), and MitoPS (WHEY: 0.061 ± 0.004; SOY: 0.061 ± 0.006; SOY + LEU: 0.063 ± 0.004%·h-1; P = 0.96) rates over the entire 360 min recovery period did not differ between treatments. Similarly, signaling through mTORC1Ser2448, p70S6kThr389, 4E-BP1Thr37/46, and rpS6Ser235/236 was similar between treatments.Conclusion: Postexercise MyoPS and MitoPS rates do not differ after co-ingestion of carbohydrate with 20 g protein from whey, soy, or leucine-enriched soy protein during 360 min of recovery from concurrent resistance- and endurance-type exercise in young, recreationally active men. This trial was registered at Nederlands Trial Register as NTR5098. [ABSTRACT FROM AUTHOR]

Background: Whey and micellar casein are high-quality dairy proteins that can stimulate postprandial muscle protein synthesis rates. How whey and casein compare with milk protein in their capacity to stimulate postprandial myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis rates during postexercise recovery is currently unknown.Objective: The objective of this study was to compare postprandial MyoPS and MitoPS rates after protein-carbohydrate co-ingestion with milk protein, whey, or micellar casein during recovery from a single bout of concurrent resistance- and endurance-type exercise in young healthy men.Methods: In a randomized, double-blind, parallel-group design, 48 healthy, young, recreationally active men (mean ± SEM age: 23 ± 0.3 y) received a primed continuous infusion of L-[ring-13C6]-phenylalanine and L-[ring-3,5-2H2]-tyrosine and ingested 45 g carbohydrate with 0 g protein (CHO), 20 g milk protein (MILK), 20 g whey protein (WHEY), or 20 g micellar casein protein (CASEIN) after a sequential bout of resistance- and endurance-type exercise (i.e., concurrent exercise). Blood and muscle biopsies were collected over 360 min during recovery from exercise to assess MyoPS and MitoPS rates and signaling through mammalian target of rapamycin complex 1 (mTORC1).Results: Despite temporal differences in postprandial plasma leucine concentrations between treatments (P < 0.001), MyoPS rates over 360 min of recovery did not differ between treatments (CHO: 0.049% ± 0.003%/h; MILK: 0.059% ± 0.003%/h; WHEY: 0.054% ± 0.002%/h; CASEIN: 0.059% ± 0.005%/h; P = 0.11). When MILK, WHEY, and CASEIN were pooled into a single group (PROTEIN), protein co-ingestion resulted in greater MyoPS rates compared with CHO (PROTEIN: 0.057% ± 0.002%/h; CHO: 0.049% ± 0.003%/h; P = 0.04). MitoPS rates and signaling through the mTORC1 pathway were similar between treatments.Conclusion: MyoPS and MitoPS rates do not differ after co-ingestion of either milk protein, whey protein, or micellar casein protein with carbohydrate during recovery from a single bout of concurrent resistance- and endurance-type exercise in recreationally active young men. Co-ingestion of protein with carbohydrate results in greater MyoPS, but not MitoPS rates, when compared with the ingestion of carbohydrate only during recovery from concurrent exercise. This trial was registered at Nederlands Trial Register: NTR5098. [ABSTRACT FROM AUTHOR]

Background: Changes in hormone levels especially testosterone and cortisol occur as a result of exercise intensity. In other words, the exercise intensity significantly influences these changes. The aim of this study was to investigate the effects of aerobics-resistance (concurrent) exercise intensities on the serum testosterone and cortisol levels in the active men. Methods: In this clinical trial, 10 healthy men were included in their combined activities in low, medium, and high levels. Different intensities (aerobic activity such as running on a treadmill at a speed of 8, 6.9, and 11.2 mph and resistance exercise on 45%, 65%, and 85% of maximum strange, maximum of six moves) were considered for all participants for unity. Blood samples were measured in three phases (baseline, immediately after exercise, and 24 hours after training contracts) at three levels. Two-way analysis of variance (ANOVA) with repeated normal data and Bonferroni post hoc test were conducted. Results: The results showed that cortisol and plasma lactate concentration was declined immediately before and 24 hours after the combined exercise with the significant level of activity (P < 0.05). Joint action at different intensities resulted in significant changes not in testosterone level (P < 0.05). Conclusion: In this study, the intensity of training as an independent variable influencing the changes in the levels of testosterone and cortisol has been recommended; so highly sportaffected hormonal changes during the combined exercise should be considered more than that in one exercise.

We aimed to determine whether creatine supplementation influences lower-limb muscle endurance following an acute bout of aerobic exercise (AE) in young healthy men. Using a randomized, double-blind, placebo-controlled crossover design, 11 men (26.5 ± 6.2 years, body mass index 26.6 ± 2.1 kg/m2),with 12 months of experience in strength training (three times/week) and AE (two times/week) were randomized to receive creatine (20 g/day plus 20 g/day maltodextrin) and placebo (40 g/day maltodextrin) for 7 days, separated by a washout period of 14 days, before performing an acute bout of AE (30 min on treadmill at 80% baseline maximum velocity) which was followed by four sets of bilateral leg extension endurance exercise using a 10-repetition maximum protocol (10 RM)). There was a significant decrease in the number of repetitions performed in the third (Placebo: −20% vs. Creatine: −22%) and fourth set (Placebo: −22% vs. Creatine: −28%) compared with the first set (p < 0.05), with no differences between creatine and placebo. Additionally, no differences were observed between creatine and placebo for the total number of repetitions performed across all four sets (Placebo: 33.9 ± 7.0 vs. Creatine: 34.0 ± 6.9 repetitions, p = 0.97), nor for total work volume (Placebo: 3030.5 ± 1068.2 vs. Creatine: 3039.8 ± 1087.7 kg, p = 0.98). Short-term creatine supplementation has no effect on lower-limb muscle endurance following an acute bout of aerobic exercise in trained young men.

Purpose: This study compared cardiorespiratory and perceptual responses to exercise using self-regulated and imposed power outputs distributed between the arms and legs.Methods: Ten males (age 21.7 ± 3.4 years) initially undertook incremental arm-crank ergometry (ACE) and cycle ergometry (CYC) tests to volitional exhaustion to determine peak power output (Wpeak). Two subsequent tests involved 20-min combined arm-leg ergometry (ALE) trials, using imposed and self-regulated protocols, both of which aimed to elicit an exercising heart rate of 160 beats min-1. During the imposed trial, arm and leg intensity were set at 40% of each ergometer-specific Wpeak. During the self-regulated trial, participants were asked to self-regulate cadence and resistance to achieve the target heart rate. Heart rate (HR), oxygen uptake ([Formula: see text]), pulmonary ventilation ([Formula: see text]), and ratings of perceived exertion (RPE) were recorded continuously.Results: As expected, there were no differences between imposed and self-regulated trials for HR, [Formula: see text], and [Formula: see text] (all P ≥ 0.05). However, central RPE and local RPE for the arms were lower during self-regulated compared imposed trials (P ≤ 0.05). Lower RPE during the self-regulated trial was related to preferential adjustments in how the arms (33 ± 5% Wpeak) and legs (46 ± 5% Wpeak) contributed to the exercise intensity.Conclusions: This study demonstrates that despite similar metabolic and cardiovascular strain elicited by imposed and self-regulated ALE, the latter was perceived to be less strenuous, which is related to participants doing more work with the legs and less work with the arms to achieve the target intensity. [ABSTRACT FROM AUTHOR]

Purpose: Sarcopenia can begin from the 4-5th decade of life and is exacerbated by obesity and inactivity. A combination of resistance exercise (RE) and endurance exercise is recommended to combat rising obesity and inactivity levels. However, work continues to elucidate whether interference in adaptive outcomes occur when RE and endurance exercise are performed concurrently. This study examined whether a single bout of concurrent RE and high-intensity interval training (HIIT) alters the satellite cell response following exercise compared to RE alone.Methods: Eight sedentary, overweight/obese, middle-aged individuals performed RE only (8 × 8 leg extensions at 70% 1RM), or RE + HIIT (10 × 1 min at 90% HRmax on a cycle ergometer). Muscle biopsies were collected from the vastus lateralis before and 96 h after the RE component to determine muscle fiber type-specific total (Pax7+ cells) and active (MyoD+ cells) satellite cell number using immunofluorescence microscopy.Results: Type-I-specific Pax7+ (P = 0.001) cell number increased after both exercise trials. Type-I-specific MyoD+ (P = 0.001) cell number increased after RE only. However, an elevated baseline value in RE + HIIT compared to RE (P = 0.046) was observed, with no differences between exercise trials at 96 h (P = 0.21). Type-II-specific Pax7+ and MyoD+ cell number remained unchanged after both exercise trials (all P ≥ 0.13).Conclusion: Combining a HIIT session after a single bout of RE does not interfere with the increase in type-I-specific total, and possibly active, satellite cell number, compared to RE only. Concurrent RE + HIIT may offer a time-efficient way to maximise the physiological benefits from a single bout of exercise in sedentary, overweight/obese, middle-aged individuals. [ABSTRACT FROM AUTHOR]

This study aimed to compare the effect of concurrent training and the addition of health education and nutrition management on body composition and health-related outcomes. Twenty-four healthy overweight females (20.42 ± 1.02 years, body mass index [BMI] 25.83 ± 3.63 kg∙m−2) were assigned to a concurrent training group (Exe, n = 12) or a concurrent training and health education group (Exe + Edu, n = 12). Both groups completed 8 weeks of concurrent training (6 days/week), whereas the Exe + Edu participants received additional health education and controlled daily energy intake within the basal metabolic rate. Body composition, serum glucose, lipids and related hormones were measured before and after intervention. After intervention, the Exe group lost 2.47 kg (±2.46) of body mass, 2.44 kg (±1.71) of total fat mass (FM), corresponding to a body fat percentage (BF%) of 2.25%. Losses of body mass, total FM and BF% in the Exe + Edu group were −5.19 ± 1.87 kg, −4.42 ± 1.83 kg and −4.33 ± 2.39%, respectively. The Exe + Edu participants had significantly greater reductions of body mass, total FM, and trunk and leg FM relative to the Exe participants (p < 0.05). Serum glucose, lipids, insulin and progesterone levels were improved in both groups without group difference. Concurrent training is an effective short-term training strategy for reducing FM and improving fasting glucose, blood lipids and related hormones. Furthermore, the combination of additional health education can achieve greater effects on weight loss and the reduction of total and regional FM, which may be a better obesity treatment method. [ABSTRACT FROM AUTHOR]

Sarcopenia is defined as the progressive loss of muscle mass with age, and poses a serious threat to the physiological and psychological health of the elderly population with consequential economic and social burdens. Chronic low-grade inflammation plays a central role in the development of sarcopenia such that it alters cellular protein metabolism to favor proteolysis over synthesis, and thereby accelerates muscular atrophy. The purpose of this review is to highlight how exercise and nutrition intervention strategies can attenuate or treat sarcopenia. Resistance exercise increases not only muscle mass but also muscle strength, while aerobic exercise is able to ameliorate the age-related metabolic disorders. Concurrent exercise training integrates the advantages of both aerobic and resistance exercise, and may exert a significant synergistic effect in the aging organism. Higher protein intakes rich in the amino acid leucine appear to restore skeletal muscle protein metabolism balance by rescuing protein synthesis in older adults. There is good reason to believe that a multimodal treatment, a combination of exercise and increased leucine consumption in the diet, can combat some of the muscle loss associated with aging. Future research is needed to consolidate these findings to humans, and to further clarify to what extent and by which mechanisms protein metabolism might be directly involved in sarcopenia pathogenesis and the multimodal treatment responses.

To evaluate the effects of a 12-wk circuit exercise training program using the floor-based exercise station (FBES) on aerobic fitness, strength, and balance in older women. Participants were divided into: FBES exercise group (EX: n=22; 68.1±6.5 yr) and a non-exercise control group (CN: n=18; 68.2±5.7 yr). EX participated in a 12-wk circuit training program, 3 d/wk for 50 min/d, consisting of warm-up exercise (10 min), circuit training (30 min), and cool-down/relaxation exercise (10 min). Twelve strength and balance exercises and 12 aerobic dance exercises were performed alternatively for 30s each with a heart rate of 100-110 bpm. CN continued normal physical activity patterns. After 12-wk, all measurements were repeated in both groups. Compared to CN, EX increased (p<0.05) arm curl (12.6%), timed up-and-go (－8.7%), 12-min walk (5.4%), predict VO2max (6.3%), sit-and-reach (24.3%), and back scratch (271.5%), but not balance parameters. Incorporating both aerobic and resistance training via the FBES improves multiple aspects of fitness but not balance. These results are similar to those from larger, more expensive hydraulic exercise machines. This study supports the efficacy of the FBES for older adults and implementation is feasible in multiple settings as it is relatively inexpensive and requires little space. [ABSTRACT FROM AUTHOR]

The majority of sports rely on concurrent training (CT; e.g., the simultaneous training of strength and endurance). However, a phenomenon called “Concurrent training effect„ (CTE), which is a compromise in adaptation resulting from concurrent training, appears to be mostly affected by the interference of the molecular pathways of the underlying adaptations from each type of training segments. Until now, it seems that the volume, intensity, type, frequency of endurance training, as well as the training history and background strongly affect the CTE. High volume, moderate, continuous and frequent endurance training, are thought to negatively affect the resistance training-induced adaptations, probably by inhibition of the Protein kinase B—mammalian target of rapamycin pathway activation, of the adenosine monophosphate-activated protein kinase (AMPK). In contrast, it seems that short bouts of high-intensity interval training (HIIT) or sprint interval training (SIT) minimize the negative effects of concurrent training. This is particularly the case when HIIT and SIT incorporated in cycling have even lower or even no negative effects, while they provide at least the same metabolic adaptations, probably through the peroxisome proliferator-activated receptor-γ coactivator (PGC-1a) pathway. However, significant questions about the molecular events underlying the CTE remain unanswered.

Hypertension is the most common, costly, and preventable cardiovascular disease risk factor. Numerous professional organizations and committees recommend exercise as initial lifestyle therapy to prevent, treat, and control hypertension. Yet, these recommendations differ in the components of the Frequency, Intensity, Time, and Type (FITT) principle of exercise prescription (Ex Rx); the evidence upon which they are based is only of fair methodological quality; and the individual studies upon which they are based generally do not include people with hypertension, which are some of the limitations in this literature. The purposes of this review are to (1) overview the professional exercise recommendations for hypertension in terms of the FITT principle of Ex Rx; (2) discuss new and emerging research related to Ex Rx for hypertension; and (3) present an updated FITT Ex Rx for adults with hypertension that integrates the existing recommendations with this new and emerging research. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effects of 20 weeks of resistance and concurrent training on psychotic and depressive symptoms, quality of life outcomes, and serum IGF-1, IGFBP-3, and brain-derived neurotrophic factor (BDNF) concentrations in patients with schizophrenia. Methods: In this blind, randomized controlled clinical trial, 34 patients with schizophrenia were assigned to one of three groups: control (CTRL, n=13), resistance exercise (RESEX, n=12), or concurrent exercise (CONCEX, n=9). Symptoms, quality of life, strength, and other variables were assessed. Results: A significant time-by-group interaction was found for the RESEX and CONCEX groups on the Positive and Negative Syndrome Scale (PANSS) total score for disease symptoms (p = 0.007), positive symptoms (p = 0.003), and on the arm extension one-repetition maximum (1RM) test (p = 0.016). In addition, significant improvements on negative symptoms (p = 0.027), on the role-physical domain of the Short Form-36 Health Survey (p = 0.019), and on the chest press 1RM test (p = 0.040) were observed in the RESEX group. No changes were observed for the other variables investigated. Conclusions: In this sample of patients with schizophrenia, 20 weeks of resistance or concurrent exercise program improved disease symptoms, strength, and quality of life. ClinicalTrials.gov: NCT01674543. [ABSTRACT FROM AUTHOR]

Concurrent training involving resistance and endurance exercise may augment the benefits of single-mode training for the purpose of improving health. However, muscle adaptations, associated with resistance exercise, may be blunted by a subsequent bout of endurance exercise, via molecular interference. High-intensity interval training ( HIIT), generating similar adaptations to endurance exercise, may offer an alternative exercise mode to traditional endurance exercise. This study examined the influence of an acute HIIT session on the molecular responses following resistance exercise in untrained skeletal muscle. Ten male participants performed resistance exercise (4 × 8 leg extensions, 70% 1 RM, ( RE)) or RE followed by HIIT (10 × 1 min at 90% HRmax, ( RE+ HIIT)). Muscle biopsies were collected from the vastus lateralis before, 2 and 6 h post- RE to determine intramuscular protein phosphorylation and mRNA responses. Phosphorylation of Akt (Ser473) decreased at 6 h in both trials ( P < 0.05). Phosphorylation of mTOR (Ser2448) was higher in RE+ HIIT ( P < 0.05). All PGC-1 α mRNA variants increased at 2 h in RE+ HIIT with PGC-1 α and PGC-1 α-ex1b remaining elevated at 6 h, whereas RE-induced increases at 2 and 6 h for PGC-1 α-ex1b only ( P < 0.05). Myostatin expression decreased at 2 and 6 h in both trials ( P < 0.05). Mu RF-1 was elevated in RE+ HIIT versus RE at 2 and 6 h ( P < 0.05). Atrogin-1 was lower at 2 h, with FOXO3A downregulated at 6 h ( P < 0.05). These data do not support the existence of an acute interference effect on protein signaling and mRNA expression, and suggest that HIIT may be an alternative to endurance exercise when performed after resistance exercise in the same training session to optimize adaptations. [ABSTRACT FROM AUTHOR]

Combining endurance and strength training in the same session has been reported to reduce the anabolic response to the latter form of exercise. The underlying mechanism, based primarily on results from rodent muscle, is proposed to involve AMPK-dependent inhibition of mTORC1 signaling. This hypothesis was tested in eight trained male subjects who in randomized order performed either resistance exercise only (R) or interval cycling followed by resistance exercise (ER). Biopsies taken from the vastus lateralis before and after endurance exercise and repeatedly after resistance exercise were assessed for glycogen content, kinase activity, protein phosphorylation, and gene expression. Mixed muscle fractional synthetic rate was measured at rest and during 3 h of recovery using the stable isotope technique. In ER, AMPK activity was elevated immediately after both endurance and resistance exercise (~90%, P < 0.05) but was unchanged in R. Thr389 phosphorylation of S6K1 was increased severalfold immediately after exercise (P < 0.05) in both trials and increased further throughout recovery. After 90 and 180 min recovery, S6K1 activity was elevated (~55 and ~110%, respectively, P < 0.05) and eukaryotic elongation factor 2 phosphorylation was reduced (~55%, P < 0.05) with no difference between trials. In contrast, markers for protein catabolism were differently influenced by the two modes of exercise; ER induced a significant increase in gene and protein expression of MuRF1 (P < 0.05), which was not observed following R exercise only. In conclusion, cycling-induced elevation in AMPK activity does not inhibit mTOR complex 1 signaling after subsequent resistance exercise but may instead interfere with the hypertrophic response by influencing key components in protein breakdown. [ABSTRACT FROM AUTHOR]

Introduction A truncated PGC-1 α splice variant ( PGC-1 α4) has been implicated in the regulation of resistance exercise ( RE)-induced muscle hypertrophy, and basal expression levels said to be augmented in response to concurrent aerobic ( AE) and RE training. Aim The current study investigated human muscle truncated and non-truncated PGC-1 α transcripts in response to both acute and chronic RE, and with or without preceding AE ( AE+ RE). Methods Ten men performed 5 weeks of unilateral AE+ RE and RE training. Before (untrained) and after (trained) this intervention, PGC-1 α transcripts were assessed in vastus lateralis muscle biopsies obtained before and 3 h after acute RE, with or without preceding AE. Additionally, samples were collected 72 h after the last exercise bout of the training programme. Results The truncated splice variant increased ( P < 0.05) its expression after acute exercise regardless of mode. However, the expression was greater ( P < 0.05) after AE+ RE than RE. Other PGC-1 α transcripts showed similar response. Truncated transcripts originated from both the alternative and proximal promoter, and AE+ RE increased PGC-1 α expression from both promoter sites. RE induced transcripts from the alternative promoter only. PGC-1 α expressions after acute exercise were comparable across isoforms in both untrained and trained muscle. Steady-state levels of isoforms were unchanged after 5-week training ( P > 0.05). Exercise-induced expression of PGC-1 α variants did not correlate with changes in muscle size or strength ( P > 0.05). Conclusion Our results do not support the view that truncated PGC-1 α coordinates exercise-induced hypertrophy in human skeletal muscle. Rather, all PGC-1 α isoforms appear to be regulated transiently in response to acute exercise and regardless of mode. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: In this study we examined oxidative stress and skeletal muscle damage resulting from acute strength, aerobic, or concurrent exercise in rats. Methods: The animals were divided into control (C), strength (SE), aerobic (AE), and combined (CE) exercise groups. They were euthanized at 3 different time-points (6, 24, and 48 h) after acute exercise. Results: SE exercise rats had increased dichlorofluorescein oxidation at 6 h post-exercise and decreased superoxide dismutase activity at all time-points. Glutathione peroxidase activity and sulfhydryl levels were increased in the AE group at 48 h post-exercise. Serum lactate dehydrogenase activity was increased in the SE and CE groups at 24 h and in the AE group at 48 h. Echo intensity was elevated at 24 h for all groups. Conclusions: Forty-eight hours was sufficient for complete recovery from oxidative stress and muscle damage in the SE and CE groups, but not in the AE group. Muscle Nerve 50: 79-86, 2014 [ABSTRACT FROM AUTHOR]

Concurrent training, a combination of endurance (EE) and resistance exercise (RE) performed in succession, may compromise the muscle hypertrophic adaptations induced by RE alone. However, little is known about the molecular signaling interactions underlying the changes in skeletal muscle adaptation during concurrent training. Here, we used an animal model to investigate whether EE before or after RE affects the molecular signaling associated with muscle protein synthesis, specifically the interaction between RE-induced mammalian target of rapamycin complex 1 (mTORC1) signaling and EE-induced AMP-activated protein kinase (AMPK) signaling. Male Sprague-Dawley rats were divided into five groups: an EE group (treadmill, 25 m/min, 60 min), an RE group (maximum isometric contraction via percutaneous electrical stimulation for 3 × 10 s, 5 sets), an EE before RE group, an EE after RE group, and a nonexercise control group. Phosphorylation of p70S6K, a marker of mTORC1 activity, was significantly increased 3 h after RE in both the EE before RE and EE after RE groups, but the increase was smaller in latter. Furthermore, protein synthesis was greatly increased 6 h after RE in the EE before RE group. Increases in the phosphorylation of AMPK and Raptor were observed only in the EE after RE group. Akt and mTOR phosphorylation were increased in both groups, with no between-group differences. Our results suggest that the last bout of exercise dictates the molecular responses and that mTORC1 signaling induced by any prior bout of RE may be downregulated by a subsequent bout of EE. [ABSTRACT FROM AUTHOR]

Concurrent resistance and aerobic exercise (CE) is recommended to ageing populations, though is postulated to induce diminished acute molecular responses. Given that contraction-induced cytokine mRNA expression reportedly mediates remunerative postexercise molecular responses, it is necessary to determine whether cytokine mRNA expression may be diminished after CE. Eight middle-aged men (age, 53.3 ±1.8 years; body mass index, 29.4 ± 1.4 kg·m−2) randomly completed (balanced for completion order) 8 × 8 leg extensions at 70% maximal strength (RE), 40 min of cycling at 55% of peak aerobic workload (AE), or (workload-matched) 50% RE and 50% AE (CE). Muscle (vastus lateralis) was obtained pre-exercise, and at 1 h and 4 h postexercise, and analyzed for changes of glycogen concentration, tumor necrosis factor (TNF)α, TNF receptor-1 and -2 (TNF-R1 and TNF-R2, respectively), interleukin (IL)-6, IL-6R, IL-1β, and IL-1 receptor-antagonist (IL-1ra). All exercise modes upregulated cytokine mRNA expression at 1 h postexercise comparably (TNFα, TNF-R1, TNF-R2, IL-1β, IL-6) ( p < 0.05). Expression remained elevated at 4 h after RE and AE ( p < 0.05), though returned to pre-exercise levels after CE ( p > 0.05). Moreover, AE and RE upregulated IL-1β and IL-1ra expression, whereas CE upregulated IL-1β expression only ( p < 0.05). Only AE reduced muscle glycogen concentration ( p < 0.05), whilst upregulating receptor expression the greatest; though, IL-6R expression remained unchanged after all modes ( p > 0.05). In conclusion, in middle-aged men, all modes induced commensurate cytokine mRNA expression at 1 h postexercise; however, only CE resulted in ameliorated expression at 4 h postexercise. Whether the RE or AE components of CE are independently or cumulatively sufficient to upregulate cytokine responses, or whether they collectively inhibit cytokine mRNA expression, remains to be determined. [ABSTRACT FROM AUTHOR]

Aim This study assessed and compared acute muscle molecular responses before and after 5-week training, employing either aerobic ( AE) and resistance exercise ( RE) or RE only. Methods Ten men performed one-legged RE, while the contralateral limb performed AE followed by RE 6 h later ( AE+ RE). Before (untrained) and after (trained) the intervention, acute bouts of RE were performed with or without preceding AE. Biopsies were obtained from m. vastus lateralis of each leg pre- and 3 h post- RE to determine mRNA levels of VEGF, PGC-1α, Mu RF-1, atrogin-1, myostatin and phosphorylation of mTOR, p70S6K, rpS6 and eEF2. Results PGC-1α and VEGF expression increased ( P < 0.05) after acute RE in the untrained, but not the trained state. These markers showed greater response after AE+ RE than RE in either condition. Myostatin was lower after AE+ RE than RE, both before and after training. AE+ RE showed higher Mu RF-1 and atrogin-1 expression than RE in the untrained, not the trained state. Exercise increased ( P < 0.05) p70S6 K phosphorylation both before and after training, yet this increase tended to be more prominent for AE+ RE than RE before training. Phosphorylation of p70S6 K was greater in trained muscle. Changes in these markers did not correlate with exercise-induced alterations in strength or muscle size. Conclusion Concurrent exercise in untrained skeletal muscle prompts global molecular responses consistent with resulting whole muscle adaptations. Yet, training blunts the more robust anabolic response shown after AE+ RE compared with RE. This study challenges the concept that single molecular markers could predict training-induced changes in muscle size or strength. [ABSTRACT FROM AUTHOR]

Objective:To evaluate the effects of 20 weeks of resistance and concurrent training on psychotic and depressive symptoms, quality of life outcomes, and serum IGF-1, IGFBP-3, and brain-derived neurotrophic factor (BDNF) concentrations in patients with schizophrenia.Methods:In this blind, randomized controlled clinical trial, 34 patients with schizophrenia were assigned to one of three groups: control (CTRL, n=13), resistance exercise (RESEX, n=12), or concurrent exercise (CONCEX, n=9). Symptoms, quality of life, strength, and other variables were assessed.Results:A significant time-by-group interaction was found for the RESEX and CONCEX groups on the Positive and Negative Syndrome Scale (PANSS) total score for disease symptoms (p = 0.007), positive symptoms (p = 0.003), and on the arm extension one-repetition maximum (1RM) test (p = 0.016). In addition, significant improvements on negative symptoms (p = 0.027), on the role-physical domain of the Short Form-36 Health Survey (p = 0.019), and on the chest press 1RM test (p = 0.040) were observed in the RESEX group. No changes were observed for the other variables investigated.Conclusions:In this sample of patients with schizophrenia, 20 weeks of resistance or concurrent exercise program improved disease symptoms, strength, and quality of life. ClinicalTrials.gov: NCT01674543.

The purpose of this study was to compare the effects of Nordic walking with conventional walking and band-based resistance exercise on functional fitness, static balance and dynamic balance in older adults. Volunteers (n = 65) were divided into four groups: Nordic walking (NW), conventional walking (CW), resistance (RES), and control. Each group performed activity 50-70 min·day-1 (warm-up 10-15 min, main exercise 30-40, and cool down 10-15 min), 3 days·week-1 (NW and CW) or 2 day·week-1 (RES) for 12 wks. Upper-body strength improved (p < 0.05) in the RES (22.3%) and the NW (11.6%) groups compared to the CW and control groups. Cardio-respiratory fitness improved more in the NW (10.9%) and CW (10.6%) groups compared to the RES and control groups. Upper- and lowerbody flexibility also improved in all exercise groups compared to the control group. There were no improvements in balance measures in any group. While all modes of exercise improved various components of fitness, Nordic walking provided the best well-rounded benefits by improving upper-body strength, cardiovascular endurance, and flexibility. Therefore, Nordic walking is recommended as an effective and efficient mode of concurrent exercise to improve overall functional fitness in older adults. [ABSTRACT FROM AUTHOR]

The objective of the study was to determine and compare the magnitude and duration of post-exercise hypotension (PEH) during free-living conditions after an acute session of concurrent water and land exercise in individuals with prehypertension and hypertension. Twenty-one men and women (aged 52 ± 10 years) volunteered for the study. Participants completed a no exercise control session, a water exercise session and a land exercise session in random order. After all three sessions, participants underwent 24-h monitoring using an Ergoscan ambulatory BP monitoring device. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were monitored to determine changes from resting values after each session and to compare the PEH responses between land and water exercises. During daytime, both land and water exercises resulted in significantly lower SBP (12.7 and 11.3 mmHg) compared to the control session (2.3 mmHg). The PEH response lasted for 24 h after land exercise and 9 h after water exercise. There was no difference in the daytime DBP for the three treatments ( P > 0.05). Although all three groups showed significant reductions during nighttime, both exercise treatments showed greater nocturnal falls in BP than the control treatment. This is the first study to show that the magnitude of the PEH response is similar for land and water exercises, although the duration of PEH may be longer for land exercise. These results suggest that water exercise is a safe alternative exercise modality for individuals with suspected and known hypertension. [ABSTRACT FROM AUTHOR]

The aim was to investigate the effects of concurrent exercise at moderate (MO) and light (LI) intensity on post-exercise hypotension (PEH). Ten women with borderline hypertension were submitted to the experimental procedure consisting of three sessions. In the MO session, the participants ran on the treadmill for 22 minutes at 65% of HRmax and then performed 5 resistance exercises against resistance corresponding to 65% of 1RM. In the LI trial, they performed a similar sequence but with intensity of 40% of HRmax and 1RM for the endurance and resistance exercise, respectively. The participants rested in a non-exercise control trial (C). The blood pressures were assessed prior and post exercising after 15, 30, 60, 90 and 120 minutes, and after four, five and six hours of recovery. A significant PEH of systolic blood pressure from the resting value was observed after the MO exercise bout at all time points, while the systolic blood pressure following the LI exercise trial decreased significantly only after the fourth hour compared to the resting value. PEH of diastolic blood pressure occurred after both LI and MO for 120 minutes and 5 hours compared to pre-exercise values, respectively. Blood pressure responses were not significantly altered during the C trial. This study suggests that a bout of concurrent endurance and resistance exercise provoked PEH in borderline hypertensive women up to six hours after exercise. However, concurrent exercise at MO intensity resulted in a longer PEH for both systolic and diastolic blood pressure compared to LI intensity. [ABSTRACT FROM AUTHOR]

The addition of aerobic exercise (AE) to a resistance exercise (RE) program (concurrent exercise, CE) can interfere with maximum muscle fiber growth achieved with RE. Further, CE appears to markedly affect the growth of myosin heavy chain (MHC) I, but not MHC IIa fibers. The mechanism responsible for this "interference" is unclear. Satellite cell (SC) responsiveness to exercise appears to influence muscle adaptation but has not yet been examined following acute concurrent exercise. Thus, we assessed the fiber-type-specific SC response to RE, AE, and CE exercise. Eight college-aged males completed the following two exercise trials: the RE trial, which consisted of unilateral leg extensions and presses (4 sets ⩾ 10 repetitions: 75% 1 repetition maximum, RM), and the AE/CE trial, which included an identical RE protocol with the opposite leg, immediately followed by subjects cycling for 90 min (60% Wmax). Muscle biopsies were obtained from the vastus lateralis before and 4 days after each session. Samples were cross-sectioned, stained with antibodies against NCAM, Ki-67, and MHC I, counterstained with DAPI, and analyzed for SC density (SC per fiber), SC activation, and fiber type. SC density increased to a greater extent following RE (38 ± 10%), compared with CE (-6 ± 8%). Similarly, MHC I muscle fiber SC density displayed a greater increase following RE (46 ± 14%), compared with AE (-7 ± 17%) and CE (-8 ± 8%). Our data indicate that the SC response to RE is blunted when immediately followed by AE, at least in MHC I muscle fibers, and possibly MHC II fibers. This suggests that the physiological environment evoked by AE might attenuate the eventual addition of myonuclei important for maximum muscle fiber growth and consequent force-producing capacity. [ABSTRACT FROM AUTHOR]

Combining endurance and strength training (concurrent training) may change the adaptation compared with single mode training. However, the site of interaction and the mechanisms are unclear. We have investigated the hypothesis that molecular signaling of mitochondrial biogenesis after endurance exercise is impaired by resistance exercise. Ten healthy subjects performed either only endurance exercise (E; 1-h cycling at ~65% of maximal oxygen uptake), or endurance exercise followed by resistance exercise (ER; 1-h cycling + 6 sets of leg press at 70-80% of 1 repetition maximum) in a randomized cross-over design. Muscle biopsies were obtained before and after exercise (1 and 3 h postcycling). The mRNA of genes related to mitochondrial biogenesis [(peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-l)α, PGC-1-related coactivator (PRC)] related coactivator) and substrate regulation (pyruvate dehydrogenase kinase-4) increased after both E and ER, but the mRNA levels were about twofold higher after ER (P < 0.01). Phosphorylation of proteins involved in the signaling cascade of protein synthesis [mammalian target of rapamycin (mTOR), ribosomal S6 kinase 1, and eukaryotic elongation factor 2] was altered after ER but not after E. Moreover, ER induced a larger increase in mRNA of genes associated with positive mTOR signaling (cMyc and Rheb). Phosphorylation of AMP-activated protein kinase, acetyl-CoA carboxylase, and Akt increased similarly at 1 h postcycling (P < 0.01) after both types of exercise. Contrary to our hypothesis, the results demonstrate that ER, performed after E, amplifies the adaptive signaling response of mitochondrial biogenesis compared with single-mode endurance exercise. The mechanism may relate to a cross talk between signaling pathways mediated by mTOR. The results suggest that concurrent training may be beneficial for the adaptation of muscle oxidative capacity. [ABSTRACT FROM AUTHOR]