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.

From the 2021 NSCA National Conference, Dr. Abbie Smith-Ryan discusses updated information, nutritional components, sex-specific considerations, and practical applications of high-intensity interval training.

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 Science and Application of High Intensity Interval Training

The Science and Application of High Intensity Interval Training

This article will present a sample program that was implemented successfully by a group of older women in competition, and discuss the general exercise principles utilized to increase BMD in postmenopausal women.

NSCA Coach 11.3 is an exercise research article providing strength coaches, considerations to design effective sports performance programs for collegiate soccer.

Brad Schoenfeld, MS, CSCS, CSPS, NSCA-CPT discusses training intensity for maximum results.

There is growing evidence that polarized endurance training is a promising method for optimizing a tactical athlete’s cardiovascular system, preparing for physical performance tests, allowing for a more full recovery during deployment, and allowing for safer return to duty after injury or deployment.

The 3-minute all-out exercise test (3MT) was developed over a decade ago and enables the estimation of time for onset of momentary fatigue for a given speed or power output exceeding critical speed (CS) or critical power (CP), respectively. The 3MT has been validated for conducting high-intensity interval training, used with load carriage prediction and prescription, and validated for shuttle running. These prescriptions are novel because they allow for standardizing exercise intensities relative to metabolic parameters as opposed to a percentage of a given maximum or reserve. Research was identified using leading search engines (e.g., PubMed, Google Scholar, and Research Gate) and citations to similar articles. The objective of this review article was to summarize research that emerged on the CS/CP concept with emphasis on applications since the advent of the 3MT. The review concludes with application of the CS/CP concept to the frequency, intensity, time, and type of exercise for exercise prescription.