The physiological response to breath holding includes bradycardia and peripheral vasoconstriction, which contrasts with that of exercise which includes tachycardia and peripheral vasodilation. This raises the question as to what the physiological response is to breath holding during exercise. During low-intensity exercise, the breath holding response of bradycardia and peripheral vasoconstriction prevails over the exercise response of tachycardia and peripheral vasodilation, but nevertheless the exercise may be sustained. Due to the lack of availability of extrinsic oxygen (O 2 ) from the atmosphere during breath holding, the energy demands can be met by increased reliance on intrinsic O 2 stores (i.e., O 2 that was in the body before the breath hold) via increased O 2 extraction at the muscle compared with exercise while breathing, or increased contributions from anaerobic energy systems. During high intensity exercise of short duration, the exercise response may prevail over the breath holding response due to the increased parasympathetic withdrawal and sympathetic drive of higher intensity exercise. If breath holding during high-intensity exercise was sustained for long enough, the breath holding response may eventually overcome the exercise response, although this may be difficult due to the inverse relationship between exercise intensity and breath hold duration.

Evidence suggests a positive relationship between physical activity, exercise, and mental health. Exercise as a treatment modality is now being considered alongside psychotherapeutic and pharmacological approaches, and the role of specifically trained exercise specialists and personal trainers is an important component of the multi-disciplinary team.

The goal of this brief review is to describe what classifies as high-intensity interval training (HIIT) and summarize the potential benefits for various populations: athletic, general, and clinical.

This PTQ article reviews scientific literature on concurrent training and examines whether combining aerobic and resistance exercise has meaningful impacts on performance. Visit the NSCA online to read more about personal training.

The purpose of this article is to give an overview and theoretical framework on the concept of periodized nutrition—with an emphasis on adequate carbohydrate intake to enhance performance.

This article highlights some of the benefits, components, and training methods involved with time-efficient training.

Knowing the risks of cold weather training is only half the battle. It is important to be familiar with a proper risk management strategy to help guide decision-making that can enhance safety and exercise performance.

The purpose of this article is to help both personal trainers and clients with seven main concepts within exercise physiology that will improve training effectiveness and assist in explaining the body’s response to exercise.

This review analyzes relevant variables involved in acute interference effects of concurrent training (CT) sessions of aerobic exercise followed by strength exercises. The aerobic exercise intensity, mode, volume, duration of recovery interval between exercises, muscle groups involved, and utilization of ergogenic aids are the variables identified in this review. High-intensity interval aerobic exercises result in more pronounced negative effects on strength-endurance exercise but not in maximal strength. Cycling results in more negative effects on strength endurance performance exercise than running. A 4-hour to 8-hour recovery interval seems to be enough to avoid interference on strength-endurance performance. Reduction in strength-endurance performance is located in muscle groups involved in both exercises. Low aerobic exercise volume (3 km) with; 18 minutes of duration does not diminish strength endurance, whereas higher volumes (5 and 7 km) with ;30 and ;42 minutes of duration, respectively, generate impairments. Caffeine, carbohydrate, and beta-alanine are not able to revert the deleterious effect on strength-endurance performance, whereas creatine and capsaicin analog supplementation are. Thus, these variables must be taken into consideration to prescribe and organize a CT session. This information may help coaches to organize exercise sessions that minimize or avoid the impairment in strength performance after aerobic exercises.

With almost one million people in the United States living with multiple sclerosis, this article aims to provide personal trainers with ideas for exercises to meet the needs of these individuals.