Does a greater time under tension when lifting lead to greater muscular size? This article addresses time under tension myths and benefits.
If you’re like me, you have spent time scouring over the internet searching for the magic formula for easy ways to make “gains.” During your search, you may have come across the term “time under tension”. Some swear by the amazing muscle building effects of time under tension, while others say it doesn’t matter.
Definition of Time Under Tension
Before we can discuss time under tension myths, let’s first clearly define what time under tension is. Time under tension is the length of time a muscle is under strain during a set. For example if you perform bench press for 10 repetitions with a 3 second eccentric portion of the lift and 1 second concentric portion of the lift, the time under tension for your chest muscles would be approximately 40 seconds.
Total Time Under Tension
You can also measure the total time under tension for a particular muscle. This is when you add up all the time that the muscle was under tension throughout each set and then calculate the total time under tension.
If we take the previous bench press example where 10 repetitions resulted in 40 seconds of time under tension, and apply that across 5 sets of bench press, we then have a total time under tension of 200 seconds.
“Time Under Load”
According to T-nation, time under tension is a bit of a misnomer. It should be thought of as “Time under load”. This is because heavier weights will create more mechanical tension in the muscle than lighter weights. Therefore, the word “tension” should be swapped out with a more generic term like “load”. This is an important distinction to make and something to keep in mind when discussing time under tension.
Before we answer the question, “does time under tension help for muscle growth or not,” lets first examine proven methods for muscle growth.
Heavy loads create mechanical tension in the muscle. Therefore, the heavier the weight, the more mechanical tension the muscles experience. If you perform a bench press with 315 lbs, the mechanical tension the muscle experiences will be greater than doing bench press with only 200 lbs. This shouldn’t be much of a surprise: if you lift heavier weights you will get bigger and stronger.
Another way muscles are thought to increase in size is via the build up of metabolites in the muscle tissue. Metabolite build up refers to hydrogen ion accumulation in the muscles. When the muscle is doing work, it starts to produce lactic acid. The acid produces excess hydrogen ions, which accumulate and cause that well known “burn” in your muscles. Here’s a link to a study showing the benefits of metabolite build up and muscle hypertrophy.
When training a muscle, the contraction of the muscle temporally cuts off the blood supply to it. This temporary occlusion of the circulation creates a hypoxic environment in the muscle. Research has shown that intermittent hypoxia in the muscle actually enhances muscle growth.
Workout volume is a tried and true way to achieve hypertrophy in muscle tissue. According to one meta analysis, exercises with multiple sets achieved greater hypertrophy compared to just doing a single set of that particular exercise. This is common knowledge: do more reps and you will experience more muscle growth.
So what does the research say about time under tension?
Multiple studies show that volume seems to be the main determining factor when it comes to muscle hypertrophy.
Here is a study that supports the hypothesis that volume is more important than time under tension for muscle growth. The study demonstrated that there was no significant difference in muscle growth between a group that trained with greater time under tension compared to a group that trained with greater volume. In addition, the group that trained with greater volume saw an average higher 1 rep maximum at the end of the training protocol.
An additional study had subjects perform two different workout routines. Group 1 performed 4 sets of 10-12 reps, group 2 performed 4 sets of 3-5 reps. Group 1 had about double to the total time under tension compared to group 2. After the 8 weeks of training was complete, both groups showed similar increases in muscle gains.
Another study featured 17 trained males that performed two different types of exercise schemes. One group performed 3 sets of 10 reps of a routine. The per set time under tension was 30-40 seconds, which equates to about 300-400 seconds of total time under tension. The second group performed a more powerlifting-esque routine doing 7 sets of 3 reps with a time under tension of about 9-12 seconds per set. This equated to a 70 second total time under tension for all the sets combined.
The results were that both groups saw the same amount of muscle hypertrophy! So even the group with more volume and more time under tension experienced the same muscle growth as the group that did less in both categories. A hypothesis for these results could be that once a threshold volume is reached, it triggers the same amount of growth as a higher volume routine. Once that threshold is reached, any additionally volume or time under tension has diminishing returns on hypertrophy.
Time under tension myths: Time under tension is more important than volume for muscle gains. FALSE
If hypertrophy is your main goal, then getting in the necessary volume is the most important training aspect you should be focusing on. Does this mean you should ditch time exercises with prolonged time under tension? Not necessarily. You do get a surge in lactate in the muscles during prolonged bouts of time under tension which helps to increase your growth hormone. Growth hormone is anabolic, and helps with your sleep quality which will help with your recovery. Growth hormone helps to burn body fat too.