Is it better to do more reps or use heavier weights? The short answer is it isn’t an either or question. For best results, focus on both. More reps with lighter weights and fewer reps with heavier weights provide a good combination strategy to help you reach new fitness goals. Here’s how.
Benefits of more reps with lighter weights
A prime benefit of high reps is the development of slow twitch or type I muscle fibers. This is important, according to Ace Fitness, because:
• Slow-twitch fibers contain mitochondria, the organelles that use oxygen to help create adenosine triphosphate (ATP), which is the chemical that actually fuels muscle contractions, and are considered aerobic. One of the benefits…
• Steady-state endurance training can help increase mitochondrial density, which improves the efficiency of how the body uses oxygen to produce ATP.
Lifting lighter weights doesn’t mean that you are taking it easy. You can still put your muscles to the test and build them stronger by making them go longer. To get the most bang for your exercise buck lift to the point of exhaustion; the last few reps should feel hard to finish. High reps help you build endurance because slow twitch fibers are slower to fatigue than fast twitch fibers
Tip: This strategy can be especially helpful if you are recovering from an injury. Use it to ease back in the game without causing further damage.
Benefits of fewer reps with higher weights
Heavier weights recruit fast-twitch or type II muscle fibers. According to Ace Fitness:
• Fast-twitch fibers can be further classified into (1) fast-twitch IIa – fast oxidative glycolytic, because they use oxygen to help convert glycogen to ATP, and (2) fast-twitch type IIb – fast glycolytic, which rely on ATP stored in the muscle cell to generate energy.
• Strength and power training can increase the number of fast-twitch muscle fibers recruited for a specific movement.
Lower reps with heavier weights help to build strength and power. Wondering about the best way to mix up your high and low plan? Marc Perry, CEO of BuiltLean offers this advice:
If your goal is to build strength
Strength – Under 6 reps (80-100% of exercise volume)
Hypertrophy (increase in muscle size) – 6-15 reps (0-20% of exercise volume)
Endurance – 15+ reps (0-10% of exercise volume)
If your goal is to lose fat
Strength – Under 6 reps (0-15% of exercise volume)
Hypertrophy – 6-15 reps (70-85% of exercise volume)
Endurance – 15+ reps (15% of exercise volume)
If your goal is to build muscle
Strength – Under 6 reps (30% of exercise volume)
Hypertrophy – 6-15 reps (60% of exercise volume)
Endurance – 15+ reps (10% of exercise volume)
The bottom line – there is value in both high and low reps. Mix it up for maximum benefit and minimal risk of injury.