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The study examined the acute neuromuscular and metabolic responses and recovery (24 and 48 h) to combined strength and endurance sessions (SEs). Recreationally endurance trained men (n= 12) and women (n= 10) performed: endurance running followed immediately by a strength loading (combined endurance and strength session (ES)) and the reverse order (SE). Maximal strength (MVC), countermovement jump height (CMJ), and creatine kinase activity were measured pre-, mid-, post-loading and at 24 and 48 h of recovery. MVC and CMJ were decreased (P< 0.05) at post-ES and SE sessions in men. Only MVC decreased in ES and SE women (P< 0.05). During recovery, no order differences in MVC were observed between sessions in men, but MVC and CMJ remained decreased. During recovery in women, a delayed decrease in CMJ was observed in ES but not in SE (P< 0.01), while MVC returned to baseline at 24 h. Creatine kinase increased (P< 0.05) during both ES and SE and peaked in all groups at 24 h. The present combined ES and SE sessions induced greater neuromuscular fatigue at post in men than in women. The delayed fatigue response in ES women may be an order effect related to muscle damage. [ABSTRACT FROM AUTHOR]

The study examined the acute neuromuscular and metabolic responses and recovery (24 and 48 h) to combined strength and endurance sessions (SEs). Recreationally endurance trained men (n= 12) and women (n= 10) performed: endurance running followed immediately by a strength loading (combined endurance and strength session (ES)) and the reverse order (SE). Maximal strength (MVC), countermovement jump height (CMJ), and creatine kinase activity were measured pre-, mid-, post-loading and at 24 and 48 h of recovery. MVC and CMJ were decreased (P< 0.05) at post-ES and SE sessions in men. Only MVC decreased in ES and SE women (P< 0.05). During recovery, no order differences in MVC were observed between sessions in men, but MVC and CMJ remained decreased. During recovery in women, a delayed decrease in CMJ was observed in ES but not in SE (P< 0.01), while MVC returned to baseline at 24 h. Creatine kinase increased (P< 0.05) during both ES and SE and peaked in all groups at 24 h. The present combined ES and SE sessions induced greater neuromuscular fatigue at post in men than in women. The delayed fatigue response in ES women may be an order effect related to muscle damage. [ABSTRACT FROM AUTHOR]

The article reports on research which was conducted to evaluate an eight week supervised, periodized mixed maximal and explosive strength training program which was added to endurance training in recreational endurance runners and was preceded by an eight week preparatory strength training period. Researchers evaluated the program with 34 subjects. They found that mixed strength training combined with endurance training may be more effective than circuit training in recreational endurance runners to benefit their overall fitness.

The article presents a study which aims to investigate the acute effects to neuromuscular and endocrine responses of variable and constant resistance exercises during hypertrophic loadings and maximal strength. The study involved thirteen young men who took part in four loadings in a counterbalanced order. The result shows that force and quadriceps electromyogram (EMG) is greater than 120 to 180 degrees knee angle during variable resistance hypertrophic loadings. The conclusion is that a bigger level of neuromuscular fatigue and larger responses occur in serum hormone concentrations after hypertrophic loading.

The article reports on research conducted to investigate acute neuromuscular and endocrine responses and recovery to a single session of combined endurance and strength loading using two loading orders. Researchers evaluated 42 male subjects. They found that both loading conditions led to significant acute reductions in maximal force production, rapid force produced in 500 milliseconds and countermovement jump height whereas no significant differences between the 2 loadings were observed.

Myllyaho, MM, Ihalainen, JK, Hackney, AC, Valtonen, M, Nummela, A, Vaara, E, Häkkinen, K, Kyröläinen, H, and Taipale, RS. Hormonal contraceptive use does not affect strength, endurance, or body composition adaptations to combined strength and endurance training in women. J Strength Cond Res 35(2): 449-457, 2021-This study examined the effects of a 10-week period of high-intensity combined strength and endurance training on strength, endurance, body composition, and serum hormone concentrations in physically active women using hormonal contraceptives (HCs, n = 9) compared with those who had never used hormonal contraceptives (NHCs, n = 9). Training consisted of 2 strength training sessions and 2 high-intensity running interval sessions per week. Maximal bilateral isometric leg press (Isom), maximal bilateral dynamic leg press (one repetition maximum [1RM]), countermovement jump (CMJ), a 3,000-m running test (3,000 m), body composition, and serum hormone levels were measured before and after training between days 1-5 of each subject's menstrual cycle. Both groups increased 1RM and CMJ: HC = 13.2% (p < 0.001) and 9.6% (p < 0.05), and NHC = 8.3% (p < 0.01) and 8.5% (p < 0.001). Hormonal contraceptive improved 3,000 m by 3.5% (p < 0.05) and NHC by 1% (n.s.). Never used hormonal contraceptive increased lean mass by 2.1% (p < 0.001), whereas body fat percentage decreased from 23.9 ± 6.7 to 22.4 ± 6.0 (-6.0%, p < 0.05). No significant changes were observed in body composition in HC. No significant between-group differences were observed in any of the performance variables. Luteinizing hormone concentrations decreased significantly (p < 0.05) over 10 weeks in NHC, whereas other hormone levels remained statistically unaltered in both groups. It seems that the present training is equally appropriate for improving strength, endurance, and body composition in women using HC as those not using HC without disrupting hypothalamic-pituitary-gonadal axis function. [ABSTRACT FROM AUTHOR]

Our primary aim was to study the effects of a 4-week preparatory resistance-training (RT) period followed by 12 weeks of 2 specific RT protocols (either hypertrophic-strength (HS) or strength-hypertrophy-power training) on inflammation markers and the possible relationship of the changes in abdominal fat and lean mass to the changes in inflammation status. A total of 82 healthy men were included in the study. Maximal concentric leg press strength (1-repetition maximum), total body lean mass, total body and abdominal fat mass, circulating high-sensitivity C-reactive protein, interleukin-6, interleukin-1 receptor antagonist (IL-1ra), monocyte chemoattractant protein 1 (MCP-1), and selected adipocytokines (resistin, adiponectin, and leptin) concentrations were measured before and after 4 (wk4) and 16 weeks (wk16) of RT. After the initial phase of RT, on wk4, abdominal and total fat mass as well as plasma leptin concentrations were significantly reduced ( p < 0.05), whereas muscle mass, IL-1ra, resistin, and MCP-1 concentrations were significantly increased ( p < 0.05). During specialized training phase, at wk16, only HS led to further reduction in abdominal and total fat mass, resistin, and leptin ( p < 0.05), whereas both training modes led to lower MCP-1 concentrations ( p < 0.05). Abdominal fat mass and circulating leptin were reduced already after 4 weeks of RT. Simultaneously, circulating MCP-1 and resistin concentrations increased, possibly as markers of muscle adaptation and regeneration. The present findings also suggest that RT with hypertrophic focus is beneficial for further reductions in abdominal fat mass and to decrease circulating inflammatory markers. [ABSTRACT FROM AUTHOR]

The primary aim of the present study was to investigate the acute gene expression responses of PGC-1 isoforms and PGC-1α target genes related to mitochondrial biogenesis ( cytochrome C), angiogenesis ( VEGF-A), and muscle hypertrophy (myostatin), after a resistance or endurance exercise bout. In addition, the study aimed to elucidate whether the expression changes of studied transcripts were linked to phosphorylation of AMPK and MAPK p38. Nineteen physically active men were divided into resistance exercise ( RE, n = 11) and endurance exercise ( EE, n = 8) groups. RE group performed leg press exercise (10 × 10 RM, 50 min) and EE walked on a treadmill (~80% HRmax, 50 min). Muscle biopsies were obtained from the vastus lateralis muscle before, 30 min, and 180 min after exercise. EE and RE significantly increased the gene expression of alternative promoter originated PGC-1α exon 1b- and 1bxs'-derived isoforms, whereas the proximal promoter originated exon 1a-derived transcripts were less inducible and were upregulated only after EE. Truncated PGC-1α transcripts were upregulated both after EE and RE. Neither RE nor EE affected the expression of PGC-1β. EE upregulated the expression of cytochrome C and VEGF-A, whereas RE upregulated VEGF-A and downregulated myostatin. Both EE and RE increased the levels of p- AMPK and p- MAPK p38, but these changes were not linked to the gene expression responses of PGC-1 isoforms. The present study comprehensively assayed PGC-1 transcripts in human skeletal muscle and showed exercise mode-specific responses thus improving the understanding of early signaling events in exercise-induced muscle adaptations. [ABSTRACT FROM AUTHOR]