Most people just bang out a set number of reps with no real regard for tempo or maintaining good target muscle contraction and form. It’s not just the amount of weight you move and number of reps that’s important for every set in order to build muscle. I mean, anyone can pick up a weight and start swinging it around. What’s crucially important for muscle growth is time under tension (TUT), but just how much attention does this muscle building factor really need?
What Does Time Under Tension Mean?
Time under tension (TUT) is simply the length of time a muscle is contracting to resist the force of a weight. For example, if someone were performing a set of bicep curls and it took them 30 seconds to complete the set, they have a total TUT of 30 seconds.
Time – Is the period during a set where the working muscle is contracting.
Tension – Is the force a muscle is producing to contract and move/hold the weight.
The idea of TUT become popular after a respected Canadian strength coach by the name of Charles Poliquin talked about TUT in his Strength and Mass Development book – The Poliquin Principles.
Charles Poliquin states that different training objectives such as muscular strength, hypertrophy (growth) and endurance are achieved optimally by different time under tension ranges.
Strength: 1 – 30 seconds
Hypertrophy: 30 -70 seconds
Muscular endurance: 70 – 100 seconds
Is TUT something that you should be overly focusing on or worrying about?
My answer is, no…
Sure, the time a muscle is under tension is important for growth, but we don’t have to complicate things by timing sets. If you’re performing your sets with good form, using a weight that’s around 75% of your 1RM in the 8 – 12 rep range, then your muscles are naturally working under sufficient time and tension optimal for muscle growth.
You’re training optimally for hypertrophy without the distraction or worry about timing. I mean, can you imagine lying under the bench press with a stopwatch or trying to keep count in your head the length of time on every set. It’s totally unnecessary and a distraction that will shift your focus away from far more important things like maintaining good form, counting reps, focusing on muscle contraction and lifting with high intensity. You’ve got enough on your plate during an intense set without having to worry about counting every second to make sure you’re working within some ‘magical’ recommended hypertrophy time zone.
When you watch pro bodybuilders train you’ll see that they are focusing on maintaining good form with intensity and counting reps, that’s it, none of them are tracking their TUT… why? Because there’s no need to for the reasons I’ve mentioned above.
It’s time to stop worrying about time under tension!
Your training should consist of a planned number of reps, sets, weight and tempo. This is all you need to concern yourself with. Basing your workout on TUT is really a waste of time in my opinion.
Best Tempo for Muscle Growth
Your TUT is directly related to your lifting tempo (lifting speed). In the table below I’ve laid out a good muscle building rep tempo. I’m not saying this is the only way you should lift, there are various effective rep and tempo protocols for hypertrophy, this is just an example of one.
4 Point Tempo
|Eccentric Contraction||Lowering the weight||2 seconds|
|Stretch Position||Bottom/starting Position||1 second|
|Concentric Contraction||Raising the Weight||2 seconds|
|Contraction Position||Top Position||1 second|
Always explode on the positive part of the movement for maximum activation of fast twitch muscle fibres. Squeeze and hold the contraction at the top of the movement for one second. Control the negative (lowering) and maintain tension on the muscle throughout the entire exercise. I can’t stress these points enough.
Control the weight… don’t let the weight control you!
If you start to get tired as you progress through your workout from set to set, people will do one of two things. Keep trying to push the same weight but with less reps, or reduce the weight and keep working in the same rep range.
If this happens, you should always choose to reduce the weight slightly and maintain your rep range. The reason for this is simple, if you start lowering reps you will be reducing your time under tension and start moving away from the optimum range for muscle hypertrophy. Also, if you keep struggling with the same weight while dropping reps your form will become sloppy. This will result in the recruitment of other muscles to compensate and takes tension off the target muscle.
To insure you’re always working in the time under tension zone optimum for muscle growth, stick to 8 – 12 reps per set with a tempo of 2-1-2-1 as shown above, this means it will take you roughly 60 seconds to perform a set and put you in the middle of the recommended hypertrophy TUT range.