I get it. It’s fun to go to the gym and bang out some quick reps. I never used to listen to people saying that it was better to go slow. Why would I go slow when I can do more reps if I go fast? Well, science has made it clear that more is not always better. The importance of quality reps over the quantity of the reps cannot be overstated. A 2011 study by Burd et al. showed that time under tension (TUT) training led to increased muscle protein synthesis (MPS). (1) The study used 2 groups. One group performed leg extensions with a slow lifting movement (6 seconds up and 6 seconds down) while the other performed them with a fast lifting movement (1 second up and 1 second down). This means that training with a slow tempo causes increased MPS, leading to more gains in muscle!
How does TUT work?
TUT essentially seeks to capitalize on the same benefits provided by high volume training using less, more controlled reps. High volume sets cause hypertrophy by causing damage to the muscle, primarily by putting a load on the muscle for a prolonged amount of time. Muscle cannot count a specific number of reps, it simply feels the load that is placed on it for a prolonged amount of time and the force of each contraction under this load. In order to increase the overload on the muscle, you can increase the load (weight) or the TUT. Lengthening the time of each rep puts more overload on the muscle per rep, allowing for increased gains in the future. In fact, due to the complete lack of momentum associated with TUT training, TUT may be even more difficult for you to perform than higher rep training without a tempo would be.
Is TUT the Secret to Gains?
One study by Mangine et al. showed similar muscle gains between two groups. (2) One group performed 4 sets of 10-12 reps while the other performed 4 sets of 3-5 reps. Essentially meaning that the two groups showed similar results, even though the group performing 10-12 reps would have had over twice the time under tension! This means that TUT is not the sole cause of hypertrophy. TUT may not be the hidden secret to gains, and I’m not claiming that it is. However, TUT is a fantastic tool that allows you to get great results even with a light weight. Maybe you are unable to go heavy due to injuries or a lack of equipment. Maybe you just want to change it up! In either case, TUT training is a great way to progressively overload your muscles, giving you a grueling workout and fantastic results, even with a lighter weight.