Workloads in Collegiate Women's Lacrosse Athletes During a Division II National Championship Season.

Sutton, PJ, Mumford, PW, and Sunderland, KL. Workloads in collegiate women's lacrosse athletes during a Division II national championship season. J Strength Cond Res 38(9): 1651-1657, 2024-A comprehensive examination of the external and internal workloads in collegiate women's lacrosse athletes has yet to be reported.

Milk or Kefir, in Comparison to Water, Do Not Enhance Running Time-Trial Performance in Endurance Master Athletes.

This study compared flavored kefir (KFR) and flavored milk (MLK) as a recovery drink in endurance master athletes. Using a randomized, placebo-controlled, non-blinded crossover design, 11 males and females completed three testing visits whilst acutely ingesting either KFR, MLK, or water as a placebo (PLA). KFR supplementation occurred for 14 days before the KFR-testing day, followed by a 3-week washout period.

Naturally Bicarbonated Water Supplementation Does Not Improve Anaerobic Cycling Performance or Blood Gas Parameters in Active Men and Women.

Unlabelled: The completion of high-intensity exercise results in robust perturbations to physiologic homeostasis, challenging the body's natural buffering systems to mitigate the accumulation of metabolic by-products. Supplementation with bicarbonate has previously been used to offset metabolic acidosis, leading to improvements in anaerobic exercise performance.

Purpose: The purpose of this study was to investigate the presence of ergogenic properties in naturally occurring low-dose bicarbonated water and their effects on anaerobic cycling performance and blood gas kinetics in recreationally active men and women.

Metabolic impact of feeding prior to a 60-min bout of moderate-intensity exercise in females in a fasted state.

Background: The metabolic impact of pre-exercise feeding of protein or carbohydrate on fat oxidation and energy expenditure rates, especially, in females, is poorly understood.

Methods: Recreationally active females ( = 15, 32 ± 10 years, 164.8 ± 5.

Effects of an external pneumatic compression device vs static compression garment on peripheral circulation and markers of sports performance and recovery.

Purpose: To identify the effects of a single 30 min partial lower leg external pneumatic compression (EPC) treatment compared to a static compression (SC) garment or a no treatment control (CTL) on markers of recovery and performance following a muscle damaging protocol.

Methods: Thirty healthy, active males (23 ± 3 years; 180.2 ± 9.

Effect of valine on myotube insulin sensitivity and metabolism with and without insulin resistance.

Population data have consistently demonstrated a correlation between circulating branched-chain amino acids (BCAA) and insulin resistance. Most recently valine catabolite, 3-hydroxyisobutyrate, has emerged as a potential cause of BCAA-mediated insulin resistance; however, it is unclear if valine independently promotes insulin resistance. It is also unclear if excess valine influences the ability of cells to degrade BCAA.

Uncarboxylated osteocalcin decreases insulin-stimulated glucose uptake without affecting insulin signaling and regulators of mitochondrial biogenesis in myotubes.

Uncarboxylated osteocalcin (uOC) is a circulating bone matrix protein, which has previously been shown to regulate glucose uptake and systemic metabolism. However, the cellular mechanism by which uOC acts has yet to be elucidated. C2C12 mouse myotubes were treated for 72 h with uOC (1-100 ng/mL).

Actions of chronic physiological 3-hydroxyisobuterate treatment on mitochondrial metabolism and insulin signaling in myotubes.

Branched-chain amino acids (BCAAs) are essential in the diet and may provide benefit for those who partake in regular physical activity and resistance training, yet circulating BCAAs have been repeatedly shown to correlate with severity of insulin resistance in obese/diseased populations. Recently, the valine catabolite 3-hydroxyisobuterate (3HIB) was shown to promote insulin resistance in skeletal muscle by increasing lipid content in vivo. The purpose of this study was to investigate the mechanistic effects of 3HIB on skeletal muscle insulin signaling, metabolism, and related gene expression in vitro.

Leucine, Palmitate, or Leucine/Palmitate Cotreatment Enhances Myotube Lipid Content and Oxidative Preference.

Branched-chain amino acids (BCAA) such as leucine stimulate favorable metabolic processes involved in lean tissue preservation and skeletal muscle metabolism. However, higher levels of circulating BCAA correlate with severity of metabolic disease (including diabetes/insulin resistance), and may result from dysregulated BCAA catabolism. Past observations have demonstrated potential interaction between BCAA and dietary fat; however, much of this relationship remains underexplored.

Metabolic effects of physiological levels of caffeine in myotubes.

Caffeine has been shown to stimulate multiple major regulators of cell energetics including AMP-activated protein kinase (AMPK) and Ca/calmodulin-dependent protein kinase II (CaMKII). Additionally, caffeine induces peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and mitochondrial biogenesis. While caffeine enhances oxidative metabolism, experimental concentrations often exceed physiologically attainable concentrations through diet.

A randomized trial of traditional and golf-specific resistance training in amateur female golfers: Benefits beyond golf performance.

Objective: Compare golf-specific resistance training (GSRT) with traditional resistance training (TRAD) with regard to golf performance and other outcome measures.

Design: Randomized controlled study.

Setting: Outpatient gym.

Characterization of the metabolic effect of β-alanine on markers of oxidative metabolism and mitochondrial biogenesis in skeletal muscle.

Purpose: β-alanine is a common component of numerous sports supplements purported to improve athletic performance through enhanced carnosine biosynthesis and related intracellular buffering. To date, the effects of β-alanine on oxidative metabolism remain largely unexplored. This work investigated the effects of β-alanine on the expression of proteins which regulate cellular energetics.

Leucine stimulates PPARβ/δ-dependent mitochondrial biogenesis and oxidative metabolism with enhanced GLUT4 content and glucose uptake in myotubes.

Leucine stimulates anabolic and catabolic processes in skeletal muscle, however little is known about the effects of leucine on peroxisome proliferator-activated receptor (PPAR) activity. This work characterized the effects of 24-h leucine treatment on metabolic parameters and protein expression in cultured myotubes. Leucine significantly increased PPARβ/δ expression as well as markers of mitochondrial biogenesis, leading to significantly increased mitochondrial content and oxidative metabolism in a PPARβ/δ-dependent manner.

Intramuscular phosphagen status and the relationship to muscle performance across the age spectrum.

Purpose: To examine age-related differences in intramuscular concentrations of adenosine triphosphate (ATP), free creatine (FCr), phosphocreatine (PCr) and total creatine (TCr) and if these differences were related to muscle performance.

Methods: Forty-two healthy, non-sedentary, males between 20 and 76 years provided muscle samples to determine [ATP], [FCr], [PCr], and [TCr]. Maximal strength and endurance were assessed and correlated with intramuscular variables.

Aging and sequential resistance exercise bout effects on housekeeping gene messenger RNA expression in human skeletal muscle.

The purpose of this study was to investigate how age and 1 week of conventional resistance exercise affects commonly used housekeeping gene (HKG) messenger RNAs (mRNAs) in skeletal muscle. Ten college-aged (18-25 years) and 10 older (60-76 years) men completed 3 lower-body resistance exercise bouts on Monday, Wednesday, and Friday, and muscle samples were obtained before bout 1 (T1), 48 hours after the first (T2) and second bouts (T3), and 24 hours after the third bout (T4). Raw Ct values indicated that β-actin and cyclophilin were more highly expressed in older vs.

Electrophoretic separation of myosin heavy chain isoforms using a modified mini gel system.

The electrophoretic separation of myosin heavy chain isoforms from muscle biopsy homogenates has been widely practiced in the field of exercise physiology to examine how intrinsic (i.e., aging) and extrinsic (i.

Pigment epithelium-derived factor (PEDF) varies with body composition and insulin resistance in healthy young people.

Context: Pigment epithelium-derived factor (PEDF) was recently implicated as a metabolic regulatory protein because plasma concentration was increased in obese or insulin resistant adults. To our knowledge, circulating PEDF values in children have not been reported. Because PEDF is a predictor of metabolic health in adults, it may have a similar impact on metabolic profiles in children.

Acute loading and aging effects on myostatin pathway biomarkers in human skeletal muscle after three sequential bouts of resistance exercise.

To determine the influence of age and resistance exercise on myostatin pathway-related genes, younger (n = 10; 28 ± 5 years) and older (n = 10; 68 ± 6 years) men underwent four testing conditions (T1-T4). A baseline (T1) muscle sample was obtained, whereas the second and third biopsies were obtained 48 hours following the first and second training sessions (T2, T3), and a final biopsy was taken 24 hours following T3. The training sessions consisted of 3 sets of 10 repetitions (80% of one repetition maximum) on leg press, hack squat, and leg extension exercises.

Megalin and androgen receptor gene expression in young and old human skeletal muscle before and after three sequential exercise bouts.

Androgen signaling occurs primarily via the androgen receptor. Megalin, a low-density lipoprotein endocytic receptor located in various mammalian tissues, has been recently shown to facilitate sex hormone–binding globulin (SHBG) steroid complexes across cell membranes. The purpose of this investigation is to determine if the megalin gene is expressed in human skeletal muscle and if present to determine how megalin and androgen receptor mRNA expression change in response to sequential exercise bouts with respect to aging.

The combined effects of exercise and ingestion of a meal replacement in conjunction with a weight loss supplement on body composition and fitness parameters in college-aged men and women.

This study was performed to evaluate the combined effect of a meal replacement and an alleged weight loss supplement (WLS) on body composition, fitness parameters, and clinical health in moderately overweight college-aged men and women. Body mass, bench press 1 repetition maximum (1RM), leg press 1RM, body composition, V(O2)max, fasting glucose (GLU), and lipid panels were evaluated before (T1) and after (T2) 8 weeks of combined resistance training (RT) and cardiovascular training (CVT). After T1, subjects were randomly assigned in a double-blind fashion to either the WLS (6 men, 7 women; 21 ± 5 years, 168 ± 8 cm, 75.

IGF-1 splice variant and IGF-1 peptide expression patterns in young and old human skeletal muscle prior to and following sequential exercise bouts.

Genes and proteins involved in insulin-like growth factor (IGF)-1 signaling are thought to be differentially expressed in older versus younger mammalian skeletal muscle following acute exercise. The purpose of this study was to examine how multiple bouts of conventional resistance training meant to elicit hypertrophy affect the mRNA expression of IGF-1EA and IGF-1EC (MGF) as well as the expression of total IGF-1 peptides in human skeletal muscle. Ten younger (18-25 years) and 10 older (60-75 years) males completed three sequential workouts (M, W, F) consisting of nine sets of lower body exercises with ten repetitions per set at an intensity of 80% of one repetition maximum.

VO2max and ventilatory threshold of trained cyclists are not affected by 28-day L-arginine supplementation.

The ergogenic effect of L-arginine on an endurance-trained population is not well studied. The few studies that have investigated L-arginine on this population have not been conducted in a laboratory setting or measured aerobic variables. The purpose of the current study is to determine if 28 days of L-arginine supplementation in trained male cyclists affects VO2max and ventilatory threshold (VT).