The interactive effect of sustained sleep restriction and resistance exercise on skeletal muscle transcriptomics in young females.

Both sleep loss and exercise regulate gene expression in skeletal muscle, yet little is known about how the interaction of these stressors affects the transcriptome. The aim of this study was to investigate the effect of nine nights of sleep restriction (SR), with repeated resistance exercise (REx) sessions, on the skeletal muscle transcriptome of young, trained females. Ten healthy females aged 18-35 yr old undertook a randomized cross-over study of nine nights of SR (5 h time in bed) and normal sleep (NS; ≥7 h time in bed) with a minimum 6-wk washout.

Gynostemma Pentaphyllum Increases Exercise Performance and Alters Mitochondrial Respiration and AMPK in Healthy Males.

This research aimed to determine the effects of Gynostemma pentaphyllum () on exercise performance, AMP-activated protein kinase (AMPK), and mitochondrial signaling in human muscle. This randomized double-blind placebo control crossover study provided placebo or 450 mg of dried leaf extract equivalent to 2.25 g of dry leaf per day for four weeks to 16 healthy untrained young males, separated by four weeks wash-out.

High-intensity training elicits greater improvements in cardio-metabolic and reproductive outcomes than moderate-intensity training in women with polycystic ovary syndrome: a randomized clinical trial.

Study Question: Does 12 weeks of high-intensity interval training (HIIT) result in greater improvements in cardio-metabolic and reproductive outcomes compared to standard moderate-intensity continuous training (MICT) in women with polycystic ovary syndrome (PCOS)?

Summary Answer: HIIT offers greater improvements in aerobic capacity, insulin sensitivity and menstrual cyclicity, and larger reductions in hyperandrogenism compared to MICT.

What Is Known Already: Exercise training is recognized to improve clinical outcomes in women with PCOS, but little is known about whether HIIT results in greater health outcomes compared to standard MICT.

Study Design, Size, Duration: This was a two-armed randomized clinical trial enrolling a total of 29 overweight women with PCOS between May 2016 and November 2019.

Cold water immersion attenuates anabolic signaling and skeletal muscle fiber hypertrophy, but not strength gain, following whole-body resistance training.

We determined the effects of cold water immersion (CWI) on long-term adaptations and post-exercise molecular responses in skeletal muscle before and after resistance training. Sixteen men (22.9 ± 4.

Enhanced skeletal muscle ribosome biogenesis, yet attenuated mTORC1 and ribosome biogenesis-related signalling, following short-term concurrent versus single-mode resistance training.

Combining endurance training with resistance training (RT) may attenuate skeletal muscle hypertrophic adaptation versus RT alone; however, the underlying mechanisms are unclear. We investigated changes in markers of ribosome biogenesis, a process linked with skeletal muscle hypertrophy, following concurrent training versus RT alone. Twenty-three males underwent eight weeks of RT, either performed alone (RT group, n = 8), or combined with either high-intensity interval training (HIT+RT group, n = 8), or moderate-intensity continuous training (MICT+RT group, n = 7).

No effect of acute beetroot juice ingestion on oxygen consumption, glucose kinetics, or skeletal muscle metabolism during submaximal exercise in males.

Beetroot juice, which is rich in nitrate (NO3 (-)), has been shown in some studies to decrease oxygen consumption (V̇o2) for a given exercise workload, i.e., increasing efficiency and exercise tolerance.

The effects of knee injury on skeletal muscle function, Na+, K+-ATPase content, and isoform abundance.

While training upregulates skeletal muscle Na(+), K(+)-ATPase (NKA), the effects of knee injury and associated disuse on muscle NKA remain unknown. This was therefore investigated in six healthy young adults with a torn anterior cruciate ligament, (KI; four females, two males; age 25.0 ± 4.

Effect of exercise training on skeletal muscle cytokine expression in the elderly.

Aging is associated with increased circulating pro-inflammatory and lower anti-inflammatory cytokines. Exercise training, in addition to improving muscle function, reduces these circulating pro-inflammatory cytokines. Yet, few studies have evaluated changes in the expression of cytokines within skeletal muscle after exercise training.

Early inflammatory and myogenic responses to resistance exercise in the elderly.

Introduction And Methods: This study compared changes in myokine and myogenic genes following resistance exercise (3 sets of 12 repetitions of maximal unilateral knee extension) in 20 elderly men (67.8 ± 1.0 years) and 15 elderly women (67.

Low muscle glycogen concentration does not suppress the anabolic response to resistance exercise.

We determined the effect of muscle glycogen concentration and postexercise nutrition on anabolic signaling and rates of myofibrillar protein synthesis after resistance exercise (REX). Sixteen young, healthy men matched for age, body mass, peak oxygen uptake (Vo(2peak)) and strength (one repetition maximum; 1RM) were randomly assigned to either a nutrient or placebo group. After 48 h diet and exercise control, subjects undertook a glycogen-depletion protocol consisting of one-leg cycling to fatigue (LOW), whereas the other leg rested (NORM).

Preexercise aminoacidemia and muscle protein synthesis after resistance exercise.

Purpose: We have previously shown that the aminoacidemia caused by the consumption of a rapidly digested protein after resistance exercise enhances muscle protein synthesis (MPS) more than the amino acid (AA) profile associated with a slowly digested protein. Here, we investigated whether differential feeding patterns of a whey protein mixture commencing before exercise affect postexercise intracellular signaling and MPS.

Methods: Twelve resistance-trained males performed leg resistance exercise 45 min after commencing each of three volume-matched nutrition protocols: placebo (PLAC, artificially sweetened water), BOLUS (25 g of whey protein + 5 g of leucine dissolved in artificially sweetened water; 1 × 500 mL), or PULSE (15 × 33-mL aliquots of BOLUS drink every 15 min).

Impact of resistance exercise training on interleukin-6 and JAK/STAT in young men.

The JAK/STAT signaling pathway is essential for myogenic regeneration and is regulated by a diverse range of ligands, including interleukin-6 (IL-6) and platelet-derived growth factor-BB (PDGF-BB). Our aim was to evaluate the responsiveness of IL-6 and PDGF-BB to intense exercise, along with STAT3 activation, before and after 12 weeks of resistance training. In young men, IL-6 and PDGF-BB protein concentrations were quantified in biopsied muscle and increased at 3 h post-exercise (17.

Effect of l-arginine infusion on glucose disposal during exercise in humans.

Purpose: We have previously shown that local infusion of a nitric oxide synthase (NOS) inhibitor attenuates increases in leg glucose uptake during exercise in humans. We have also shown that infusion of the NOS substrate, l-arginine (l-Arg), increases glucose clearance, although the mechanisms involved were not determined. A potential mechanism for NO-mediated glucose disposal is via interactions with NOS and the energy sensor AMP-activated protein kinase (AMPK).

Nutrient provision increases signalling and protein synthesis in human skeletal muscle after repeated sprints.

The effect of nutrient availability on the acute molecular responses following repeated sprint exercise is unknown. The aim of this study was to determine skeletal muscle cellular and protein synthetic responses following repeated sprint exercise with nutrient provision. Eight healthy young male subjects undertook two sprint cycling sessions (10 × 6 s, 0.

N-Acetylcysteine infusion does not affect glucose disposal during prolonged moderate-intensity exercise in humans.

There is evidence that reactive oxygen species (ROS) signalling is required for normal increases in glucose uptake during contraction of isolated mouse skeletal muscle, and that AMP-activated protein kinase (AMPK) is involved. The aim of this study was to determine whether ROS signalling is involved in the regulation of glucose disposal and AMPK activation during moderate-intensity exercise in humans. Nine healthy males completed 80 min of cycle ergometry at 62 +/- 1% of peak oxygen consumption ( V(O(2)peak).

Exercise-induced histone modifications in human skeletal muscle.

Skeletal muscle adaptations to exercise confer many of the health benefits of physical activity and occur partly through alterations in skeletal muscle gene expression. The exact mechanisms mediating altered skeletal muscle gene expression in response to exercise are unknown. However, in recent years, chromatin remodelling through epigenetic histone modifications has emerged as a key regulatory mechanism controlling gene expression in general.

Acute signalling responses to intense endurance training commenced with low or normal muscle glycogen.

We have previously demonstrated that well-trained subjects who completed a 3 week training programme in which selected high-intensity interval training (HIT) sessions were commenced with low muscle glycogen content increased the maximal activities of several oxidative enzymes that promote endurance adaptations to a greater extent than subjects who began all training sessions with normal glycogen levels. The aim of the present study was to investigate acute skeletal muscle signalling responses to a single bout of HIT commenced with low or normal muscle glycogen stores in an attempt to elucidate potential mechanism(s) that might underlie our previous observations. Six endurance-trained cyclists/triathletes performed a 100 min ride at approximately 70% peak O(2) uptake (AT) on day 1 and HIT (8 x 5 min work bouts at maximal self-selected effort with 1 min rest) 24 h later (HIGH).

Effect of consecutive repeated sprint and resistance exercise bouts on acute adaptive responses in human skeletal muscle.

We examined acute molecular responses in skeletal muscle to repeated sprint and resistance exercise bouts. Six men [age, 24.7 +/- 6.

Consecutive bouts of diverse contractile activity alter acute responses in human skeletal muscle.

We examined acute molecular responses in skeletal muscle to divergent exercise stimuli by combining consecutive bouts of resistance and endurance exercise. Eight men [22.9 +/- 6.

Brief intense interval exercise activates AMPK and p38 MAPK signaling and increases the expression of PGC-1alpha in human skeletal muscle.

From a cell signaling perspective, short-duration intense muscular work is typically associated with resistance training and linked to pathways that stimulate growth. However, brief repeated sessions of sprint or high-intensity interval exercise induce rapid phenotypic changes that resemble traditional endurance training. We tested the hypothesis that an acute session of intense intermittent cycle exercise would activate signaling cascades linked to mitochondrial biogenesis in human skeletal muscle.

Fat adaptation followed by carbohydrate restoration increases AMPK activity in skeletal muscle from trained humans.

We have previously reported that 5 days of a high-fat diet followed by 1 day of high-carbohydrate intake (Fat-adapt) increased rates of fat oxidation and decreased rates of muscle glycogenolysis during submaximal cycling compared with consumption of an isoenergetic high-carbohydrate diet (HCHO) for 6 days (Burke et al. J Appl Physiol 89: 2413-2421, 2000; Stellingwerff et al. Am J Physiol Endocrinol Metab 290: E380-E388, 2006).

Skeletal muscle adaptation and performance responses to once a day versus twice every second day endurance training regimens.

We determined the effects of a cycle training program in which selected sessions were performed with low muscle glycogen content on training capacity and subsequent endurance performance, whole body substrate oxidation during submaximal exercise, and several mitochondrial enzymes and signaling proteins with putative roles in promoting training adaptation. Seven endurance-trained cyclists/triathletes trained daily (High) alternating between 100-min steady-state aerobic rides (AT) one day, followed by a high-intensity interval training session (HIT; 8 x 5 min at maximum self-selected effort) the next day. Another seven subjects trained twice every second day (Low), first undertaking AT, then 1-2 h later, the HIT.