Do High Reps and Light Weights Get You Lean?

Want to get ripped? Like shredded? Be able to see all your abs, and see where your different chest and shoulder muscles separate?
Then you need to use lighter weights and high reps!
NO!
This is completely wrong.
If you don’t change anything else about your activity, and more importantly your eating habits, you will simply achieve NOTHING! Worse than that, if you seriously lay off the heavier weights, you’ll probably lose a load of strength too.
Similarly, these people will also say the opposite is true: If you want to get big and bulky, you should lift heavy weights for low reps.
That is not AS BAD as the other advice, but it is still wrong.
How Getting Lean Actually Works
If you want to get lean/ripped/shredded then you need to lose body fat.The thing that stops you looking shredded is the fat that is covering your muscles. This fat obscures them and makes them less visible. When you’ve got less of it, you’ll see more definition in your muscles, more separation between different muscles, and you’ll look more muscular (even though you’re actually smaller!)
I’m going to sound like a broken record (as it seems I am saying the same thing in every post), but the only way to lose body fat is by being in a calorie deficit. That means eating fewer calories in a day than your body requires to maintain its current weight and your current activity level. The bigger the gap, the faster you lose fat.
There are several ways to get into a calorie deficit:
- Eat fewer calories so that you’re eating below your maintenance calories.
- Increase your activity by doing more exercise until it exceeds the amount of calories you’re taking in per day.
- Some combination of the two above.
Simply lowering the weights you use and lifting them for more reps WILL NOT somehow burn fat from your body.
If you start lifting weights for sets of 12 when you previously lifted them for sets of 5, you might actually BUILD MORE MUSCLE. This is because you’re changing the stimulus on your muscles, and it can be easier to get stronger in a new rep range. Getting stronger + calorie surplus = building muscle. What won’t happen is fat loss if you are not in a calorie deficit.
Heavy Weights and Low Reps to Build Muscle
To build muscle, you should simply focus on increasing the load on your muscles over time whilst being in a calorie surplus and getting enough protein. If the calorie surplus or the protein isn’t there, you’ll probably not build any muscle (unless you’re a complete beginner, and even then this phase doesn’t last long).
Lifting heavy weights is a good idea, but what’s more crucial is that you’re increasing the amount of work your muscles have to do workout to workout, week to week. This can be done without changing the weights at all.
Adding more reps of the same weight will help build muscle. More sets with the same reps will help build muscle, and more weight but the same reps and sets will also work.
What’s important is the VOLUME (weight x reps x sets).
If weekly volume is going up while you’re in a calorie surplus and eating enough protein, muscle will be built (probably a lot slower than you’d like!)
Simply switching to a heavier weight, and lifting it for less reps, won’t necessarily build muscle, even if you ARE in a calorie surplus and getting enough protein.
Consider this scenario
Trainee 1: Weight of 50 kg, lifted for 3 sets of 10 reps = 1,500kg total volume.
Trainee 2: Weight of 65kg, lifted for 5 sets of 1 rep = 325kg total volume.
Both of these trainees are physically very similar. Let’s say they’re identical twins with a similar level of training experience.
My money would be on trainee 1 being more likely to build muscle in a calorie surplus. This is because the total volume lifted is greater. It’s also easier to improve a set of 10 than it is to improve a set of 1.
Going from 1 all out rep, to 2 all out reps of the same weight is very difficult. Adding 1 rep to a set of 10 is much easier. Similarly, adding 2.5kg to a weight you can lift for 1 rep is much more difficult than adding 2.5kg to a weight you can lift for 10 reps.
The trainee working in the higher rep range is more likely to be able to easily increase the load on their muscles. If this occurs while a calorie surplus and enough protein is present, you will build muscle.
Conclusion: Ignore “Bro” Advice!
If you want to lose fat, it’s all about calories, not weights or reps.
If you want to gain muscle, this is actually easier with higher rep sets. What actually matters is increasing the VOLUME of weight lifted, over time. This is easier to do if you’re working with higher rep sets (8 – 12 reps).