Heavier weights vs. more reps is as hot a debate as sweet vs. salty. So, you’re not alone if you’ve ever wondered which is better for building strength.

Let’s see if we can settle things so that you win.

“Strength training has a long list of incredible benefits,” says exercise physiologist Sharon Gam, CSCS.

To name a few, it can decrease the risk of many chronic diseases, increase mental and physical health, improve brain function, boost mood, energy, and self-esteem, plus decrease chronic pain, and much more, she says.

“Any time your muscles are working against some kind of resistance — whether for a lot of reps or high weight — you’re reaping some of those benefits,” she says.

Ultimately, how many reps you should be cranking out at a time will depend only on your specific strength goal. If you’re trying to improve muscular endurance, for example, the recommended rep and set count will be different than if you’re trying to put on muscle mass.

Here are some general rep and set rules from Gam.

  • To increase overall power output and high end strength numbers: 5 sets of 3–5 reps, 2 or more minutes rest between sets
  • To build muscle mass or lose weight: 4 sets of 6–12 reps, 90 seconds to 2 minutes rest between sets
  • To improve muscular endurance: 3 sets of 12–20 reps, 90 seconds rest between sets

If you’re new to lifting, however, Gam says it’s best to start with 2 or 3 sets of 12 to 15 reps per exercise. “This is a good starting point because it gives you plenty of opportunities to practice form,” she says.

Simply put, enough weight to challenge you.

“If you lift weights that don’t challenge you, your body doesn’t get the message to get stronger, fitter, and healthier,” explains Gam. “You want to pick a weight that makes the last 2 to 3 reps of every set difficult,” she says.

But you don’t want to go so heavy that you’re failing any reps — especially if you’re new to lifting. (The one caveat here is that advanced lifters may intentionally train to failure, but the general population doesn’t need to worry about this).

Gam notes that when the last two reps of each set stop being challenging, that’s when you know it’s time to go up in weight. “If you’ve been challenged by the weight, you should need a rest before you feel ready to start the next set. If the weight is too light, you’ll feel like you could immediately do another set.”

Just be sure to go up in small increments. Your goal is to squeeze out big results from little changes. (FYI: It also helps to include a proper warmup and cooldown).

For most people, continuously going up and up and up is adequate for warding off a fitness plateau — that dreaded no man’s land where your body adapts to your routine, and you no longer make progress.

But it may not be enough to ward off boredom! No shade, but some exercisers get bored doing the same thing plus or minus 5 pounds day in and day out.

If you relate, consider switching up other factors.

You could, for example:

  • slow down the tempo
  • increase the intensity
  • decrease rest between sets
  • change up the order of exercises in your routine
  • switch up the weighted implement you’re using

This technique of switching up different factors in a workout routine is known as the progressive overload principle. And it’s a sure-fire way to get stronger, according to strength and conditioning coach Jake Harcoff, MS, CSCS, CISSN.

“Many people fail to increase their strength due to not progressively overloading their tissues,” he says. “It’s common to see someone go to the gym regularly for years and never change their programming. Simply put, if you are doing the same workout over and over again, with no substantial increases in load, sets, or frequency, positive adaptations will diminish.” Not ideal if you’ve got goals you want to meet!

“The key thing to remember when it comes to progressive overload is that it MUST challenge you to change you,” he says.

…No, not in the same session — but in the same workout program!

For long-term progress and to keep things interesting, you might try something known as periodization training. It involves incorporating heavyweight, low rep training combined with lightweight, high rep training. By switching up the weights, sets, and reps on different days or weeks you’re able to keep your workout routine both effective and fun, according to Nathan Jones, a physical therapist and Strongman competitor.

“If you’ve been doing 5 sets of 5 squats and can’t add weight or get an extra rep, drop the weight and go to 5 sets of 8, or add weight and go to 3 sets of 5,” he says.

Basically, imagine your sets and reps as a wavelength continuously going up and down.

There’s nothing inherently magical about changing things up this way. “Personally, I think it’s more psychological than anything,” Jones says. “Doing the same rep range every single time you lift gets boring. So, doing something different helps you maintain motivation, and subsequently, keeps your effort high.”

Mixing it up a bit to keep yourself motivated and to see progress — whatever your goal — will go a long way.

Ultimately, there’s no wrong decision here, according to Jones. He says whether you’re lifting more weight or cranking out more reps you’re nudging your body toward continually improved fitness and strength.

That said, if you have a specific goal you’re after (lose weight, bulk up, prepare your bod for a Spartan race, etc.) you should let those goals dictate your rep range. Then, pick a weight that challenges you when you have to lift it that many times.