Effects of exercise in a cold environment on transcriptional control of PGC-1α.

Peroxisome proliferator-activated receptor-α coactivator-1α (PGC-1α) mRNA is increased with both exercise and exposure to cold temperature. However, transcriptional control has yet to be examined during exercise in the cold. Additionally, the need for environmental cold exposure after exercise may not be a practical recovery modality.

Impact of hot and cold exposure on human skeletal muscle gene expression.

Many human diseases lead to a loss of skeletal muscle metabolic function and mass. Local and environmental temperature can modulate the exercise-stimulated response of several genes involved in mitochondrial biogenesis and skeletal muscle function in a human model. However, the impact of environmental temperature, independent of exercise, has not been addressed in a human model.

Transcriptional control, but not subcellular location, of PGC-1α is altered following exercise in a hot environment.

The purpose of this study was to determine mitochondrial biogenesis-related mRNA expression, binding of transcription factors to the peroxisome proliferator-activated receptor-γ coactivator 1-α (PGC-1α) promoter, and subcellular location of PGC-1α protein in human skeletal muscle following exercise in a hot environment compared with a room temperature environment. Recreationally trained males (n = 11) completed two trials in a temperature- and humidity-controlled environmental chamber. Each trial consisted of cycling in either a hot (H) or room temperature (C) environment (33 and 20°C, respectively) for 1 h at 60% of maximum wattage (Wmax) followed by 3 h of supine recovery at room temperature.

The effects of constant vs. variable workload cycling on performance and perception.

Background: The purpose of this study was to determine whether constant load (CL) cycling or variable load (VL) cycling stimulates different physiological and psychological responses.

Methods: Recreationally-trained male cyclists (N.=8, age 32±5 yr, weight 75.

Human skeletal muscle mRNAResponse to a single hypoxic exercise bout.

Background: The ability to physically perform at high altitude may require unique strategies to acclimatize before exposure. The effect of acute hypoxic exposure on the metabolic response of the skeletal muscle may provide insight into the value of short-term preacclimatization strategies.

Objective: To determine the human skeletal muscle response to a single acute bout of exercise in a hypoxic environment on metabolic gene expression.

Running performance, pace strategy, and thermoregulation differ between a treadmill and indoor track.

Self-paced time trials have long been used as an indicator of running performance. The purpose of this study was to examine if potential physiological and thermoregulatory differences between treadmill and track running would alter performance in a self-paced 10-km time trial. Ten (n = 10) recreationally trained male distance runners (age: 32 ± 6 years, height: 177 ± 6 cm, body mass: 76 ± 11 kg, % body fat: 14.

Physiological and psychological responses to outdoor vs. laboratory cycling.

The purpose of this study was to determine the physiological and psychological responses to laboratory vs. outdoor cycling. Twelve recreationally trained male cyclists participated in an initial descriptive testing session and 2 experimental trials consisting of 1 laboratory and 1 outdoor session, in a randomized order.

The performance effect of early versus late carbohydrate feedings during prolonged exercise.

The purpose of this study was to determine how the timing of isoenergetic carbohydrate feedings during prolonged cycling affects performance in a subsequent 10-km cycling time trial. Recreationally trained male cyclists (n = 8; age, 34.5 ± 8.