This excerpt briefly discusses components of interval workouts, including recommended volume and intensity, to increase overall endurance in athletes.

In this session from 2019 Coaches Conference, Paul Laursen, co-author of the book “Science and Application of High-Intensity Interval Training: Solutions to the Programming Puzzle,” explains the physiological targets of high-intensity interval training and how to design and manipulate variables for a variety of applications.

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

This article discusses the ratings of perceived exertion (RPE) scales and how to educate older clients to utilize them, as well as how to monitor and safely progress their training intensity.

The purpose of this article is to review the related literature that has explored the influence of resistance training programs on the onset of fatigue and muscular power as it relates to non-contact high-intensity intermittent sports, in order to provide suggestions for creating same-day training programs.

The purpose of this article is to discuss the health and occupational implications of firefighters not currently meeting the National Fire Protection Association (NFPA) aerobic capacity recommendations.

This article reviews the use of heart rate as a way to program cardiovascular exercise.

The loading intensity a person chooses depends on his or her goals and training status (i.e., whether the person is a trained athlete or a sedentary individual). Ultimately, the number of repetitions you can perform at a given intensity or load determines the effects of training on strength develop.

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.

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.