How To Challenge Muscles Without Adding Load: Time Under Tension

Progressive overload is the principle that in order to increase muscular size, strength or endurance, you must continually increase the demands placed on those muscles. Most commonly, this involves increasing load (amount of weight being moved), or increasing the amount of reps at a given load. However, this is not the only way that progressive overload can be achieved. Utilizing Time Under Tension (TUT) techniques can be a useful tool to progressively overload muscles without the addition of weight. Simply put, TUT is the amount of time during a set that the working muscles are under stress. Here are a few ways to increase TUT:

1. Slow the eccentric phase

The eccentric phase of a movement is characterized by the lengthening of the target muscles under load. Eccentric muscle contractions are a more passive contraction (working with gravity) and by slowing down and controlling this portion of the movement, time under tension will be increased, making the movement more difficult. Here is an example of a slowed eccentric phase in a back squat:

2. Pause at the peak of the concentric phase

The concentric phase of a movement is characterized by the shortening of the target muscles (i.e standing up in a squat). Adding a pause for 2+ seconds at the peak of the concentric phase will directly increase time under tension for a given movement. Here is an example of a pause at the peak of the concentric phase during a pull up:

3. Don't lockout or pause at the top between reps

When resting or pausing between reps by locking out, the muscles are under very minimal, if any, tension. Eliminating these short periods of rest will increase the time under tension and intensity of a given exercise. Here is an example of a no lockout back squat:

4. Utilize drop sets

Drop sets are often used in hypertrophy training and are a great way to increase volume and time under tension for a given exercise. This technique can be performed by completing an exercise at a given weight to failure, immediately dropping to a lower weight, and completing another set to failure (multiple "drops" can be performed). Here is an example of a dumbbell row drop set:

5. Add an isometric hold for unilateral exercises

An isometric contraction is classified as an activated, contracted muscle that undergoes no change in length (no movement). Similar to a concentric hold, adding isometric holds between reps for unilateral (single sided or single limb) exercises can be a great way to increase the tension of a given exercise. This can be completed during alternating reps, or by completing all reps on a single side while holding the opposite side in an isometric contraction. Here is an example of an alternating isometric hold for a lateral raise: