To time or not to time in your workout?


If you are looking to improve body tone, strength or muscular endurance you may have considered how many sets and reps you are doing but have you considered the rest time you take between your sets?

How much rest you take between your sets can affect the way your body responds to the training demands placed upon it. Specifically, the rest time between sets can affect the way your muscles and metabolic system adapt to the exercises you do.

If you are looking to improve muscular endurance or tone it is best to do 3-4 sets with a weight that you can do 15-20+ repetitions. In this case it’s typically suggested you take 1 minute rest between sets.

In contrast, if you’re looking to increase power you’re more likely to do 5-6 sets of 2-4 repetitions. In this case you would be looking to keep quality in the lifts and ensure that each rep is done with explosive power. Therefore, you would choose a rest time of 3 minutes. Why 3 minutes? This is the time required for the majority of ATP and creatine phosphate stores to be replenished. ATP and creatine phosphate make up the energy system designed to provide quick energy and power to muscles.

If you’re looking to increase strength a 2 minute rest time is often suggested.

So what should you do with this information? Get out the stopwatch during all your workouts? Well, yes, sometimes, especially if you are only just starting out in your workout ‘career’.

However, recent research from the European Journal of Sports Science (by De Salles and his pals) looked at the effects of measuring rest time between sets and letting people choose their own self-selected rest period (without using a watch). The results suggested that when rest time was self-selected the number of reps in each set were not compromised… people are able to feel when they are ready to start the next set. Furthermore, when a self-selected rest period was used rest time was lower than when using a timer leading to a shorter workout.

The take home message? Using a self-selected rest time may decrease the overall time of your workout without compromising the quality of your weights session. One limitation though – if you’re new to training I recommend that you still get out a stop watch to help you understand the effects of different length recovery periods. Just remember, 1 minute rest for endurance/body tone; 2 minutes rest for strength development; 3 minutes rest between sets for power training.

By Dr Laurence Houghton (PhD Sports Science)