The Effect of Resisted Sprint Training on Acceleration: A Systematic Review and Meta-Analysis.

Resisted sprint (RS) training, such as sled or parachute towing, is commonly used for sprint training among field sport athletes. While RS training is frequently employed by athletes and coaches, there is little research on its benefits, especially compared to unresisted running (UR) training programs with similar training volumes. This systematic review and meta-analysis compared the effectiveness of RS training on acceleration compared to UR training.

Metabolic Heat Production Modulates the Cardiovascular Drift-V̇O 2max Relationship Independent of Aerobic Fitness in Women.

Introduction/purpose: The purpose of this study was to test the hypothesis that cardiovascular (CV) drift and associated decrements in maximal oxygen uptake (V̇O 2max ) are greater in high-fit compared with low-fit women during exercise at the same %V̇O 2max , but comparable at the same rate of metabolic heat production.

Methods: Six high-fit (HI) and six low-fit (LO) women cycled in 35°C for 15 or 45 min at the same relative intensity (60% V̇O 2max ; 15REL and 45REL) or fixed rate of heat production (500 W; 15FX and 45FX), immediately followed by a graded exercise test to measure V̇O 2max . The separate 15- and 45-min trials permitted measurements of V̇O 2max over the same time interval as CV drift.

Acute work rate adjustments during high-intensity interval training in a hot and temperate environment.

Heart rate drifts upward over time during interval exercise and during exercise in hot conditions. As such, work rate must be lowered to maintain target heart rate. The purpose was to characterize acute work rate adjustments during high-intensity interval training based on target heart rate.

Effect of Work-to-Rest Cycles on Cardiovascular Strain and Maximal Oxygen Uptake during Heat Stress.

Cardiovascular drift-a progressive increase in heart rate (HR) and decrease in stroke volume (SV) during prolonged exercise-is exacerbated by heat stress and thermal strain, and often accompanied by a decrease in work capacity (indexed as maximal oxygen uptake [V.O]). To attenuate physiological strain during work in the heat, use of work:rest ratios is recommended by the National Institute for Occupational Safety and Health.

Effect of Ice Slurry Beverages on Voluntary Fluid Intake and Exercise Performance.

Ng, J and Wingo, JE. Effect of ice slurry beverages on voluntary fluid intake and exercise performance. J Strength Cond Res 37(6): e376-e383, 2023-Voluntary intake of cold fluid is greater than warm fluid as a result of more favorable palatability, resulting in better maintenance of hydration status and improved exercise performance.

Physical demands and physiological strain of American football referees while officiating.

Objectives: Certain occupations are associated with greater risk of triggering a sudden cardiac event because of high levels of physical exertion and extreme thermal environments in which they occur. The extent to which sports officials--particularly high school (HS) American football referees--experience these conditions is unknown. Forty-six male HS officials (72% White/Caucasian; age = 48 ± 12 years, body mass index = 31.

Roundtable on Preseason Heat Safety in Secondary School Athletics: Heat Acclimatization.

Objective: To provide best-practice recommendations for developing and implementing heat-acclimatization strategies in secondary school athletics.

Data Sources: An extensive literature review on topics related to heat acclimatization and heat acclimation was conducted by a group of content experts. Using the Delphi method, action-oriented recommendations were developed.

Menstrual cycle effects on cardiovascular drift and maximal oxygen uptake during exercise heat stress.

Aim: Compared to other modulators of physiological strain associated with exercise heat stress, hyperthermia results in the greatest magnitude of cardiovascular (CV) drift and associated decrements in maximal oxygen uptake ([Formula: see text]).

Purpose: To determine if elevated core temperature in the luteal phase (LP) of the menstrual cycle results in greater CV drift and reductions in [Formula: see text] versus the follicular phase (FP).

Methods: Seven women performed 15- and 45-min cycling bouts on separate occasions (60% [Formula: see text], 35 °C) followed by a [Formula: see text] test during the FP and LP.

Cardiovascular Drift and Maximal Oxygen Uptake during Running and Cycling in the Heat.

Introduction: Greater cardiovascular (CV) drift occurs during cycling compared to running in temperate conditions. CV drift also corresponds to proportional reductions in maximal oxygen uptake (V˙O2max) during heat stress. Whether exercise mode differentially affects CV drift-and accompanying declines in V˙O2max-during heat stress is uncertain.

Fan cooling after cardiovascular drift does not reverse decrements in maximal oxygen uptake during heat stress.

Cardiovascular (CV) drift, the progressive increase in heart rate (HR) and decrease in stroke volume (SV) during constant rate, moderate intensity exercise, is related to reduced maximal oxygen uptake (V̇O) during heat stress. Once it has already occurred, it is unknown whether the detrimental effects of CV drift on V̇O can be reversed. This study tested the hypothesis that fan cooling after CV drift has occurred attenuates decrements in V̇O associated with CV drift.

Practical Hydration Solutions for Sports.

Personalized hydration strategies play a key role in optimizing the performance and safety of athletes during sporting activities. Clinicians should be aware of the many physiological, behavioral, logistical and psychological issues that determine both the athlete's fluid needs during sport and his/her opportunity to address them; these are often specific to the environment, the event and the individual athlete. In this paper we address the major considerations for assessing hydration status in athletes and practical solutions to overcome obstacles of a given sport.

Agreement between supine and standing bioimpedance spectroscopy devices and dual-energy X-ray absorptiometry for body composition determination.

Background: Research comparing bioimpedance spectroscopy (BIS) to dual-energy X-ray absorptiometry (DXA) is limited, especially with newer BIS devices that take measures in a standing position instead of the traditional supine position.

Purpose: The purpose of this study was to compare a standing BIS device (BIS ) and a supine BIS device (BIS ) to DXA for measuring body fat percentage (BF%), fat mass (FM) and fat-free mass (FFM) in a cohort of male and female subjects displaying a wide range of ages and BMI levels.

Methods: Ninety-five subjects (30 ± 15 years, 170 ± 8·0 cm, 72·6 ± 14·8 kg) participated in the study.

Effect of Ice Slurry Ingestion on Cardiovascular Drift and V˙O2max during Heat Stress.

Unlabelled: External body cooling by fan airflow mitigates the decrease in maximal oxygen uptake (V˙O2max) associated with cardiovascular (CV) drift during cycling in hot conditions. It remains unknown whether internal body cooling via ice slurry ingestion elicits a similar response.

Purpose: This study aimed to test the hypothesis that ice slurry ingestion attenuates the magnitude of CV drift and accompanying decrement in V˙O2max during heat stress.

An Evaluation of Select Physical Activity Exercise Classes on Bone Metabolism.

Weight-bearing physical activity can optimize bone mass early in life and prevent the development of osteoporosis. However, less is known about the potential benefits of non-weight-bearing activities. The purpose of this study was to assess the efficacy of structured physical activity classes on bone metabolism.

Ice Slurry Ingestion and Physiological Strain During Exercise in Non-Compensable Heat Stress.

Introduction: Precooling with ice slurry ingestion attenuates the increase in rectal temperature (Tre) during subsequent running and cycling. It remains unclear how this cooling method affects physiological strain during work while wearing protective garments. This study investigated the effect of ice slurry ingestion on physiological strain during work in hot conditions while wearing firefighter protective clothing.

Effect of Magnesium Carbonate Use on Repeated Open-Handed and Pinch Grip Weight-Assisted Pull-Ups.

The purpose was to determine if pull-up performance was affected by the use of chalk (100% magnesium carbonate) during open-handed and pinch grip weight-assisted pull-ups (WAPU) in recreationally-trained rock climbers. Furthermore, the reliability of open-handed and pinch grip WAPU was also investigated. Recreationally-active volunteers (n = 9) completed six counterbalanced trials.

Precooling and Warm-Up Effects on Time Trial Cycling During Heat Stress.

Background: Heat stress limits endurance exercise performance. Combining precooling and warm-up prior to endurance exercise in the heat may exploit the benefits of both strategies while avoiding the potential negative consequences of each. This study tested the hypothesis that precooling combined with warm-up improves time trial cycling performance in the heat relative to either treatment alone.

Comparison of Bioelectrical Impedance Analysis and Dual-Energy X-Ray Absorptiometry for Estimating Bone Mineral Content.

The purpose of this study was to validate single-frequency hand-to-foot bioelectrical impedance analysis (HFBIA) for estimating bone mineral content (BMC) using dual-energy X-ray absorptiometry as the criterion measure in healthy men and women aged 18-40 years. A total of 80 men and women participated in this study. BMC was estimated on the same day using HFBIA and dual-energy X-ray absorptiometry.

Impact of upper body precooling during warm-up on subsequent time trial paced cycling in the heat.

Objectives: The purpose of this study was to test the hypothesis that cooling the upper body during a warm-up enhances performance during a subsequent 16.1-km simulated cycling time trial in a hot environment.

Design: Counterbalanced, repeated measures design.

Heart Rate Variability and Training Load Among National Collegiate Athletic Association Division 1 College Football Players Throughout Spring Camp.

Flatt, AA, Esco, MR, Allen, JR, Robinson, JB, Earley, RL, Fedewa, MV, Bragg, A, Keith, CM, and Wingo, JE. Heart rate variability and training load among National Collegiate Athletic Association Division 1 college football players throughout spring camp. J Strength Cond Res 32(11): 3127-3134, 2018-The purpose of this study was to determine whether recovery of cardiac-autonomic activity to baseline occurs between consecutive-day training sessions among positional groups of a collegiate football team during Spring camp.

Impact of Measured vs. Predicted Residual Lung Volume on Body Fat Percentage Using Underwater Weighing and 4-Compartment Model.

Nickerson, BS, Esco, MR, Bishop, PA, Schumacker, RE, Richardson, MT, Fedewa, MV, Wingo, JE, and Welborn, BA. Impact of measured vs. predicted residual lung volume on body fat percentage using underwater weighing and 4-compartment model.

Validity of Selected Bioimpedance Equations for Estimating Body Composition in Men and Women: A Four-Compartment Model Comparison.

Nickerson, BS, Esco, MR, Bishop, PA, Schumacker, RE, Richardson, MT, Fedewa, MV, Wingo, JE, and Welborn, BA. Validity of selected bioimpedance equations for estimating body composition in men and women: a four-compartment model comparison. J Strength Cond Res 31(7): 1963-1972, 2017-The purpose of this study was to compare body fat percentage (BF%) and fat-free mass (FFM) values from bioelectrical impedance analysis (BIA) equations to values determined from a 4-compartment (4C) model.

Combined facial heating and inhalation of hot air do not alter thermoeffector responses in humans.

The influence of thermoreceptors in human facial skin on thermoeffector responses is equivocal; furthermore, the presence of thermoreceptors in the respiratory tract and their involvement in thermal homeostasis has not been elucidated. This study tested the hypothesis that hot air directed on the face and inhaled during whole body passive heat stress elicits an earlier onset and greater sensitivity of cutaneous vasodilation and sweating than that directed on an equal skin surface area away from the face. Six men and two women completed two trials separated by ∼1 wk.