Counting reps refers to the number of times you perform a given exercise in a set, while time under tension refers to the total amount of time that a specific muscle or group of muscles is under strain during an exercise.
It’s difficult to say definitively which approach is better, as both have their own benefits and can be useful in different contexts. Here are some potential pros and cons of each approach:
- Can be a good way to measure progress, as you can track how many reps you can do with a given weight over time.
- Can help you focus on good form, as you may be more likely to pay attention to your technique when counting reps.
- May be easier to track, as you can simply count the number of reps you do rather than trying to estimate how long you held a certain position.
- May not be as effective at improving muscle endurance, as you may be able to do more reps with a lighter weight than you would be able to if you were focusing on time under tension.
- May not be as effective at building muscle mass, as you may not be able to create as much metabolic stress (a key driver of muscle growth) with a lighter weight.
Time under tension
- Can be a good way to improve muscle endurance, as you will be keeping your muscles under strain for a longer period of time.
- Can be a good way to build muscle mass, as you can create more metabolic stress by holding a position with a given weight for a longer period of time.
- May be more effective at improving muscle control and stability, as you will be asking your muscles to maintain a position for a longer period of time.
- May be more difficult to track, as you will need to estimate how long you held a given position.
- May be more difficult to measure progress, as it can be hard to compare the total time under tension from one workout to another.
- May be more tempting to cheat on form in order to hold a position for a longer period of time.
Ultimately, the best approach for you will depend on your goals and what works best for you personally. Some people may find that they prefer counting reps, while others may find that time under tension works better for them. It’s also worth noting that both approaches can be useful, and you may want to incorporate elements of both into your training.