Grow muscle with this underrated training technique

by Carol Saldanha on Sunday 11 February 2024

6 min read

Introducing... 'Time Under Tension'

This less flashy but effective training principle has been the foundation of strength training since the beginning of free weights. Even though the concept of time under tension (TUT) and its impact on muscle growth plays a crucial role in muscle building, it often doesn't get the credit it deserves.

Let’s break down time under tension and find out how to use it to maximise muscle growth.

What does time under tension mean?

Time under tension (TUT) is the total time your muscles are under strain during an exercise. In a nutshell, it’s about focusing on the tempo of your strength training, not the weight.

For example, if you’re doing a chin-up, your rep might look like this:

  • 2 seconds up
  • 1-second rest at the top
  • 2 seconds down.

That equals 5 seconds of time under tension per rep.

Why does that matter? Well, different tempos (i.e. time under tension) impact the result of your workout. For example, shorter TUT builds power and strength, and longer TUT builds muscle mass and endurance.

If you want to keep your muscles under tension for longer, slow down one of the phases of an exercise (more on that later), or introduce isometric holds. In practice, that might mean slowly moving the barbell from the bench press closer to your chest or holding a plank for a minute. Because when you hold a movement, you keep the muscle length unchanged and under tension.

What are the benefits of TUT?

The brilliant thing about TUT is its versatility. Changing the tempo of an exercise can provide different benefits.

More muscle power

Power training focuses on developing explosive strength – bursts of energy for short-duration activities.

During power training, the TUT typically ranges from 5 to 10 seconds per set. This means that each repetition of the exercise is performed with maximal speed, allowing for activation of muscle fibres that generate power.

Increased muscle strength

This type of TUT training is about increasing muscle strength and the ability to lift heavy loads. It requires high levels of energy because you're pushing or pulling the heaviest weights you can manage.

TUT ranges from 10 to 30 seconds. This timeframe allows for enough time under tension to challenge the muscles and stimulate strength gains.

Better muscle endurance

If you want to build muscular endurance, you need to expose your muscles to longer periods of tension. This is how you can train your body to repeat a movement for a longer period. In TUT terms, this means you need to complete a set of exercises in more than 60 seconds.

How does TUT assist with muscle growth?

Another great benefit of TUT is muscle growth. Science shows muscle growth, or hypertrophy, happens when the rate of building new muscle proteins (muscle protein synthesis) is greater than the rate of breaking down existing proteins (muscle protein breakdown).

Extending time under tension stimulates more muscle protein synthesis due to the degree of muscle damage generated from the training stimulus. When combined with sufficient protein and caloric intake, you can considerably improve the rate of muscle growth.

How do you use TUT methods for muscle growth?

Exercises have two phases: lifting (concentric) and lowering (eccentric). Muscle growth happens in the lowering phase. So, the key to optimising hypertrophy is slowing down the tempo of this phase. This means your muscles will be under tension for extended periods.

Considering all exercises have a lifting and lowering phase, you can increase TUT while doing any of your go-to movements. For example, try to slow down your lowering phase of during squats or incorporate pauses during reps.

You can even play with pause times. Start with a three-second hold, then throw in a five-second pause the following session. Don’t be afraid to get creative! Experimenting with set tempo and sneaking in pauses is a great way to keep training fresh and interesting.

How to perform TUT effectively and safely

-Firstly, ease into it. You will be working with weights, so gradually increase them over several weeks.

-Focus on the hardest part of each exercise, usually the part where your muscles are lengthening (e.g. the bottom of a squat)

-Take extended breaks between sets.

-Rest up. Even though TUT exercises are slow, don't skip your rest day.

-Mix up your muscle groups each training session to give them the best chance to recover.

If these tips are tricky to wrangle, don’t tackle them alone. Get help to effectively increase (or decrease) tempo and ensure your exercises are performed correctly with instructions and a workout plan designed by a fitness professional. Book a PT session to start working towards your training goals with a Coach today.

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