The effect of repetition tempo on cardiovascular and metabolic stress when time under tension is matched during lower body exercise

The Ultimate Guide for Selecting Repetition Tempos

“…Although repetition volume is two times greater during the “Fast” condition, this allows TUT to be matched (60 seconds), and proximity to muscular failure will be much more similar between conditions. There are many possible explanations for why faster repetitions stimulate greater cardiorespiratory stress, but we speculate that the more frequent and forceful contractions result in a greater pressor response and feedback from the group 3/4 afferent neurons (2).…”

“…Here, relative intensity and repetition volume are matched, but TUT is two times as high during the “Slow” condition (60 vs. 30 seconds), which will result in greater physiological stress because the sets are simply more difficult and are performed closer to failure (2). Interestingly, when TUT and effort are matched, the opposite effect is observed because HR, blood lactate, oxygen consumption, and energy expenditure are greater when repetition tempos are faster (2). Let's make a minor adjustment to the previous example:…”

“…Original research in this area demonstrated that slower tempos stimulated greater increases in HR, ventilation, oxygen consumption, energy expenditure, local hypoxia, blood lactate, and “anabolic” hormone concentration (2). However, a common confounding variable among these studies is that researchers did not match TUT and/or proximity to muscular failure ( i.e.…”

“…When designing resistance training (RT) programs, fitness professionals provide overload to their clients by systematically manipulating several training variables such as external load, repetition range, volume, frequency, rest periods, exercise selection, order of exercises, and velocity of muscle actions (1). The latter variable is known as repetition tempo (2), which also has been characterized as repetition duration (3). For example, if a lifter performs a 2-second eccentric phase followed by a 1-second concentric phase, this would be written as a 2/1-second tempo or a 3-second duration.…”

“…Returning to the previous example, if the lifter does not pause between repetitions (0 seconds), but executes a 1-second pause between the eccentric and concentric phases, the repetition tempo would be written as 2/1/1/0 seconds, and the duration would now be 4 seconds. Regardless of how repetition tempo is written and described, it is often discussed with the number of repetitions completed per set because both variables have a direct effect on set duration, which is commonly referred to as time under tension (TUT) (2). Assuming that sets are performed close to momentary muscular failure, it is now agreed on that hypertrophy occurs at a wide range of repetitions per set (3-35 reps) with corresponding relative external loads (30%-90% 1-repetition maximum [1-RM]) (5).…”