Campbell, Jennifer, and Shaun M. Phillips. “The Effects of Two Weeks Low-Volume Self-Regulated High-Intensity Interval Training on Cardiorespiratory Fitness, Exercise Enjoyment, and Intentions to Repeat”. Journal of Human Sport and Exercise 16, no. 2 (April 1, 2021): 411–423. Accessed June 12, 2024. https://www.jhse.ua.es/article/view/2021-v16-n2-training-cardiorespiratory-fitness-exercise-enjoymen.