Maximize muscle gains by leveraging the concept of time under tension, writes fitness expert Dean Hodgkin.

Time is a critical factor in the realm of fitness, dictating everything from the duration of workouts, to the intervals between sets and the timing of sessions. It can even influence the kit you buy, with an increasing number of products like the latest adjustable dumbbells designed to save on both time and space. But amidst these considerations, there’s a lesser-known concept that holds even greater significance: time under tension (TUT).

What is time under tension?

Time under tension refers to the duration for which a muscle is under strain during an exercise. It includes the time spent during the concentric (shortening) phase, eccentric (lengthening) phase, and any pauses or isometric holds within the movement.

Benefits of TUT

Manipulating TUT by adjusting the speed of repetitions or incorporating pauses can influence the effectiveness of an exercise in terms of muscle endurance, strength, and hypertrophy (muscle growth). Increasing TUT can lead to greater muscle fatigue and stimulate more muscle fibers, potentially promoting greater gains in strength and size over time.

How does TUT work?

The basic tenet of muscle building revolves around using resistance training to place target muscles under a mechanical load that causes structural breakdown. As a response to that, your body automatically promotes protein synthesis in the muscles. Introducing TUT increases the challenge, dials up the stress and can enhance your progress.

Studies at McMaster University in Ontario compared results from sets of leg extensions performed at a slow tempo of 6 seconds up and 6 seconds down, to speed repetitions of 1 second up and 1 second down. Participants performed 3 sets with a two-minute rest interval between sets, resulting in a six times as much time under tension in the slow-tempo group. Muscle biopsies taken post-exercise revealed significantly greater increases in myofibrillar protein synthesis and intracellular anabolic signalling in those following the TUT protocol, indicating potential for greater improvements in muscle mass.

bearded man in vest performing bicep exercise in the gym

How to increase time under tension

The premise is very simple, more time equals more muscle, and that can be achieved in many ways. Here are a few examples to get you started, but don’t be afraid to be creative and design your own. 

  1. Increase your volume
    The easiest adjustments are to increase your numbers of sets and/or reps, for example, instead of the standard 3 sets of 10 reps, you could try 4 sets of 12 reps or perhaps 5 sets of 15 reps.
  2. Squeeze more rounds in
    If you’re following a metabolic conditioning routine or an old-school dumbbell circuit, cut down your rest time so you can squeeze in another round of exercises in your allotted time. For example 30 seconds effort followed by 30 seconds recovery would become 45 seconds on and 15 seconds off, or even 50 seconds and 10 seconds.
  3. Lift weights slowly
    Using the lift speed four-digit format, take the pace down to 4-0-4-0, so four-second concentric, followed by four-second eccentric. Those zeros are crucial, as they mean no resting at the start or finish of the exercise, thereby achieving the goal of keeping the target muscle continuously engaged.
  4. Pause mid-lift
    Add variety by introducing an isometric contraction mid-range of motion on either the negative phase, the lift phase or even both. Stopping halfway down (or up) on a squat, and staying there for 3 seconds in a static hold, significantly increases the workload on your glutes, quads and hamstrings.
  5. Add pulse reps
    Building on the paused repetitions, and just to ensure you wring out every drop of energy from your muscles, instead of remaining static at the mid-point, try a few little pulses up and down before completing the movement.

The best time under tension protocol

Research has established that faster concentric speeds provide a better stimulus for neural adaptations that lead to greater strength gains, while increasing the eccentric time under tension helps to promote muscular hypertrophy. Clearly, then, combining both is the optimum approach, giving you twice the bang for your buck, so focus on tempo options like 5-0-1-0, 6-0-2-0 and 8-0-3-0.

Understanding tempo instructions for workouts

Most gym-goers will be familiar with the four-digit format used by trainers to dictate speed of movement. Each number indicates the length of time in seconds to execute a specific phase of an exercise. For example, let’s consider the bench press and a 3-1-2-1 count.

The first number is the eccentric portion of the lift, which in a bench press would be lowering the bar down to your chest, so in our case this would be for a count of 3 seconds.

The second digit represents the halfway point of the exercise. With the bench press that would be when the bar is on your chest, so hold it for 1 second before pushing it back up.

The time for the concentric portion of the exercise, i.e. the lift, is indicated by the third number, so that would be pressing the bar off your chest for a count of 2 seconds.

The fourth number governs how long you rest at the end of the movement before beginning the next rep, in our example waiting 1 second before again lowering the bar to your chest.