When it comes to strength-training, you may be wondering whether it’s more important to be able to lift heavier weights or to do more repetitions using lighter weights.

This debate has raged on for years, and although different people have their own opinions about one method of building strength compared to another, there is no scientifically clear-cut answer to the question of whether light or heavy weights are better. That’s because when it comes to the benefits of strength-training, there are a number of factors that impact the effectiveness of your efforts to strengthen your muscles.

The consensus among many fitness professionals is that it’s most important to lift “enough.” What exactly does that mean? It means you need to do enough to challenge your muscles to grow stronger. So, if you can do more reps with lighter weights, you’ll still see results even if the weight you’re lifting isn’t incredibly heavy. It may take more of your time to get the job done, but the job will still get done.

According to researchers, it doesn’t matter whether weights are heavy or light, as long as you lift to the point of fatigue. Total work volume (reps x weight) is what matters most. Keep in mind that light and heavy are relative terms, and even when you’re lifting lighter weights, some real weight is necessary to lift to the point of fatigue. You can’t simply do a bunch of reps with 2 pound weights and expect to see results.

One recent study published in the Journal of Applied Physiology set out to determine if lifting light or heavy weights had an impact on developing muscle strength. The researchers had 49 men with previous weight-training experience follow a program for 12 weeks. Half of them lifted light weights – meaning they could do sets of 20 – 25 reps at that weight before failing. The other half lifted heavy weights – meaning they could only get in 8 – 12 reps before failing. The results showed that both groups of men increased their strength and muscle size similarly.

Of course, this is just a small study and more research is needed, but it does back up the notion that getting stronger over time involves a combination of volume (# of reps) and weight.

This is good news for those who shy away from lifting heavy weights, either due to age, injury or simply lack of interest, but who still want to increase muscle strength. It’s also useful information for those who want to avoid hitting a plateau – a point where your body doesn’t get the same results doing the same thing you’ve always done. The best way to avoid a fitness plateau is to keep changing things up. So sometimes you may want to lift heavier weights and sometimes you’ll want to use lighter weights but do more reps.

Whether you’re lifting heavy or doing more reps with lighter weights, it’s important to focus on your form. If your form starts to go, you not only risk injury but you may not be getting the benefits you expect because you’re not working your muscles properly. It’s easier to focus on form when you’re lifting lighter weights because each rep isn’t pushing your body to its limits, but once you get up there in reps, it’s important to concentrate on form as you start to fatigue.

Sources:

http://jap.physiology.org/content/early/2016/05/09/japplphysiol.00154.2016

http://www.fitnessmagazine.com/workout/lose-weight/build-strength/does-it-matter-how-heavy-you-lift/

http://www.mensfitness.com/training/build-muscle/if-you-want-build-muscle-and-gain-strength-lift-lighter-weights-more-reps