People ask me all the time,
“how heavy should I go when I am doing strength training?”
“how heavy should I go when I am doing strength training?”
The quick answer is this. When you are just starting (the first eight weeks), don't worry about it. Your goal is consistency. Focus on technique and showing up.
Once you get past this phase, 'reps in reserve' is an important concept.
Reps in Reserve
Reps in reserve describes how many more reps you could have done. If you get done with a set of 10 repetitions and think to yourself, "There is no way I could have done another rep," you had zero reps in reserve. I don't want this for you. For most people, it's too heavy and unnecessary.
If you get done with 10 repetitions and think to yourself, "I could have done 20 more reps," well then you had 20 reps in reserve and this is far too easy. I don't want that for you either.
After your first 8 weeks of training is done, aim for 5 reps in reserve. This means the speed of your movement slows down a little bit. Once you have been training for 16 or more weeks, aim for 2-3 reps in reserve.
You can apply this concept to every exercise to help you gauge the weight you will use for each exercise. For example, you would go heavier on a row than a curl but still use the reps in reserve concept to pick the right weight for you.
Justin — What's Up With the 30-Second Rest Periods? The Longer Answer
Honestly, it's probably not long enough of a rest period. Let me explain.
Every strength training variable is related and leads to a specific outcome. Take the load or amount of weight you are lifting as an example. If you lift heavy weights (think 1-6 repetitions) this guarantees a number of things:
The main outcome you will get will be increased strength and improved bone mineral density (this can happen at other rep ranges too).
You will do a limited number of repetitions. The heavier the weight is relative to your max, the fewer reps you can do.
Bar or dumbbell speed will be slow. The lighter the weight, the faster you can move it.
You will need longer rest periods to recover (2-3 minutes).
Even with the ten reps I typically prescribe, which is moderate weight (about 70% of your max), you will still need to have a decent rest period to recover. If you are approaching that 2-3 reps in reserve you are working hard and will need time to recover so you can repeat the effort.
So, if you get to the 30-second rest period and think you don't need it, think about increasing the weights. I am often resting 60-90 seconds and sometimes even 3 minutes if I am doing 6 reps or less in strength training.
So if you want to see adaptations, getting stronger, retaining or gaining muscle, you need to make sure you are putting in a good effort. If you are pushing yourself with 2-3 reps in reserve, then you will need rest to recover to repeat the effort.
-Justin