Low and high rep training to failure may build similar muscle size, but strength gains vary by load
Original: Can 3-5 Reps Truly Maximize Growth? (New Study)
TL;DR
Evidence suggests training to failure with 3-5 reps and 20-25 reps produces comparable hypertrophy, though strength outcomes differ and research limitations remain.
Quick Answer
The new study shows that training with 3-5 reps to failure produces similar muscle growth as 20-25 reps when sets and rest time are equated, with average muscle thickness increases of 7.4-8.5%. However, the evidence is not yet strong enough to confirm this definitively due to small sample sizes and confounding factors in other studies.
Claims (20)
1. For people who already lift weights, pushing to muscle failure with either light or heavy weights gives the same muscle growth and strength improvements after 12 weeks.
2. Whether you lift lighter weights or heavier weights until you can't do any more reps, both ways give you the same muscle growth and strength gains if you're already used to training.
3. When lifting lighter weights, pushing until you can't do any more reps helps build more muscle than stopping early. But with heavier weights, pushing to failure doesn't give much extra muscle growth compared to stopping a bit sooner.
4. When lifting lighter weights, pushing until you can't lift anymore helps build bigger muscles, but this doesn't happen with heavier weights. Heavier weights always build more strength than lighter ones, no matter how hard you push.
5. Lifting lighter weights many times until you can't do any more builds as much muscle as lifting heavy weights a few times in people who already exercise regularly.
6. When people who are already fit push themselves as hard as they can during weight training, it doesn't matter if they lift heavy weights for a few reps or lighter weights for many reps—both ways build muscle about the same.
7. When you lift weights until you can't anymore, you build similar muscle size no matter how heavy the weights are, but lifting heavier weights makes you stronger and faster at moving them than lighter weights.
8. If you do the same total amount of lifting, whether you lift heavy weights for fewer reps or lighter weights for more reps, you'll build about the same amount of muscle as a beginner.
9. Lifting heavier weights makes you stronger and improves your brain-muscle connection more than lifting lighter weights, even if you do the same total amount of work and build the same muscle size.
10. Lifting weights until you can't lift anymore makes muscles grow bigger no matter how heavy the weights are, but using heavier weights builds more strength than lighter ones.
11. Doing slow, gentle weight training can build muscle and make you just as strong as lifting heavy weights quickly.
12. Lifting heavy weights with fewer reps and longer breaks builds more muscle and strength than lifting lighter weights with more reps and shorter breaks in men who already work out.
13. Lifting very heavy weights a few times with long breaks builds more muscle and strength faster than lifting lighter weights many times with short breaks, when the total amount of lifting isn't the same.
14. When untrained young men lift weights with different heavy loads but equal total work, their chest muscles grow about the same amount—around 10-11% bigger.
15. For women who don't usually lift weights, doing lots of lighter reps or fewer heavy reps both build similar muscle size and make you stronger after two months.
16. If you lift heavy weights for fewer reps and lighter weights for more reps but do the same total work, you'll build about the same muscle size, but you'll get stronger faster with the heavy weights.
17. If you do the same total amount of weightlifting work, lifting heavy weights with longer breaks and lifting lighter weights with shorter breaks both build muscle about the same, but lifting heavy gives you more strength.
18. When you lift weights, doing a few heavy reps makes you stronger, doing lots of light reps helps your stamina, and doing a medium amount builds bigger muscles.
19. How many times you lift a weight affects what your body gets better at: lifting heavy weights a few times builds strength, lifting lighter weights many times builds endurance, and doing a middle amount builds muscle size.
20. When you lift weights until you can't anymore, you build about the same muscle size no matter how many reps you do, but doing more reps makes you stronger than doing fewer reps.
Key Takeaways
- •Problem: It's unclear how few reps you can do per set and still build muscle as much as possible.
- •Core methods: Training with 3-5 reps to failure using heavy weights, Training with 20-25 reps to failure using light weights
- •How methods work: Both methods involve lifting until you can't do more reps, which stresses muscles to grow; heavy weights with low reps and light weights with high reps can work similarly if you push to failure.
- •Expected outcomes: Similar muscle size increases (around 7-8% thickness growth) for both rep ranges after 9 weeks.
- •Implementation timeframe: Results can be seen after 9 weeks of training twice per week.
Overview
Determining the minimum reps needed to maximize hypertrophy per set is unclear. This study investigates whether 3-5 reps can produce growth comparable to higher reps, with equated volume and rest, using ultrasound and biopsy measurements.
Key Terms
How to Apply
- 1.Choose exercises like leg press and leg extension to train specific muscles.
- 2.For one side (e.g., left leg), perform 3-5 reps per set using a heavy load that allows only 3-5 reps before failure; do 3 sets with 2 minutes rest between sets.
- 3.For the other side (e.g., right leg), perform 20-25 reps per set using a light load that allows only 20-25 reps before failure; do 3 sets with 2 minutes rest between sets.
- 4.Train each exercise twice per week for 9 weeks, adjusting loads as needed to stay in the target rep ranges.
- 5.Ensure you train to volitional failure (cannot complete another rep) with strong effort in all sets.
After 9 weeks, you may see similar increases in muscle thickness (around 7-8%) for both rep ranges, though individual results may vary due to factors like genetics and consistency.
Studies from Description (30)
Unprocessed Studies (2)
Additional Links (7)
Claims (20)
1. For people who already lift weights, pushing to muscle failure with either light or heavy weights gives the same muscle growth and strength improvements after 12 weeks.
2. Whether you lift lighter weights or heavier weights until you can't do any more reps, both ways give you the same muscle growth and strength gains if you're already used to training.
3. When lifting lighter weights, pushing until you can't do any more reps helps build more muscle than stopping early. But with heavier weights, pushing to failure doesn't give much extra muscle growth compared to stopping a bit sooner.
4. When lifting lighter weights, pushing until you can't lift anymore helps build bigger muscles, but this doesn't happen with heavier weights. Heavier weights always build more strength than lighter ones, no matter how hard you push.
5. Lifting lighter weights many times until you can't do any more builds as much muscle as lifting heavy weights a few times in people who already exercise regularly.
6. When people who are already fit push themselves as hard as they can during weight training, it doesn't matter if they lift heavy weights for a few reps or lighter weights for many reps—both ways build muscle about the same.
7. When you lift weights until you can't anymore, you build similar muscle size no matter how heavy the weights are, but lifting heavier weights makes you stronger and faster at moving them than lighter weights.
8. If you do the same total amount of lifting, whether you lift heavy weights for fewer reps or lighter weights for more reps, you'll build about the same amount of muscle as a beginner.
9. Lifting heavier weights makes you stronger and improves your brain-muscle connection more than lifting lighter weights, even if you do the same total amount of work and build the same muscle size.
10. Lifting weights until you can't lift anymore makes muscles grow bigger no matter how heavy the weights are, but using heavier weights builds more strength than lighter ones.
11. Doing slow, gentle weight training can build muscle and make you just as strong as lifting heavy weights quickly.
12. Lifting heavy weights with fewer reps and longer breaks builds more muscle and strength than lifting lighter weights with more reps and shorter breaks in men who already work out.
13. Lifting very heavy weights a few times with long breaks builds more muscle and strength faster than lifting lighter weights many times with short breaks, when the total amount of lifting isn't the same.
14. When untrained young men lift weights with different heavy loads but equal total work, their chest muscles grow about the same amount—around 10-11% bigger.
15. For women who don't usually lift weights, doing lots of lighter reps or fewer heavy reps both build similar muscle size and make you stronger after two months.
16. If you lift heavy weights for fewer reps and lighter weights for more reps but do the same total work, you'll build about the same muscle size, but you'll get stronger faster with the heavy weights.
17. If you do the same total amount of weightlifting work, lifting heavy weights with longer breaks and lifting lighter weights with shorter breaks both build muscle about the same, but lifting heavy gives you more strength.
18. When you lift weights, doing a few heavy reps makes you stronger, doing lots of light reps helps your stamina, and doing a medium amount builds bigger muscles.
19. How many times you lift a weight affects what your body gets better at: lifting heavy weights a few times builds strength, lifting lighter weights many times builds endurance, and doing a middle amount builds muscle size.
20. When you lift weights until you can't anymore, you build about the same muscle size no matter how many reps you do, but doing more reps makes you stronger than doing fewer reps.
Claims (20)
1. For people who already lift weights, pushing to muscle failure with either light or heavy weights gives the same muscle growth and strength improvements after 12 weeks.
2. Whether you lift lighter weights or heavier weights until you can't do any more reps, both ways give you the same muscle growth and strength gains if you're already used to training.
3. When lifting lighter weights, pushing until you can't do any more reps helps build more muscle than stopping early. But with heavier weights, pushing to failure doesn't give much extra muscle growth compared to stopping a bit sooner.
4. When lifting lighter weights, pushing until you can't lift anymore helps build bigger muscles, but this doesn't happen with heavier weights. Heavier weights always build more strength than lighter ones, no matter how hard you push.
5. Lifting lighter weights many times until you can't do any more builds as much muscle as lifting heavy weights a few times in people who already exercise regularly.
6. When people who are already fit push themselves as hard as they can during weight training, it doesn't matter if they lift heavy weights for a few reps or lighter weights for many reps—both ways build muscle about the same.
7. When you lift weights until you can't anymore, you build similar muscle size no matter how heavy the weights are, but lifting heavier weights makes you stronger and faster at moving them than lighter weights.
8. If you do the same total amount of lifting, whether you lift heavy weights for fewer reps or lighter weights for more reps, you'll build about the same amount of muscle as a beginner.
9. Lifting heavier weights makes you stronger and improves your brain-muscle connection more than lifting lighter weights, even if you do the same total amount of work and build the same muscle size.
10. Lifting weights until you can't lift anymore makes muscles grow bigger no matter how heavy the weights are, but using heavier weights builds more strength than lighter ones.
11. Doing slow, gentle weight training can build muscle and make you just as strong as lifting heavy weights quickly.
12. Lifting heavy weights with fewer reps and longer breaks builds more muscle and strength than lifting lighter weights with more reps and shorter breaks in men who already work out.
13. Lifting very heavy weights a few times with long breaks builds more muscle and strength faster than lifting lighter weights many times with short breaks, when the total amount of lifting isn't the same.
14. When untrained young men lift weights with different heavy loads but equal total work, their chest muscles grow about the same amount—around 10-11% bigger.
15. For women who don't usually lift weights, doing lots of lighter reps or fewer heavy reps both build similar muscle size and make you stronger after two months.
16. If you lift heavy weights for fewer reps and lighter weights for more reps but do the same total work, you'll build about the same muscle size, but you'll get stronger faster with the heavy weights.
17. If you do the same total amount of weightlifting work, lifting heavy weights with longer breaks and lifting lighter weights with shorter breaks both build muscle about the same, but lifting heavy gives you more strength.
18. When you lift weights, doing a few heavy reps makes you stronger, doing lots of light reps helps your stamina, and doing a medium amount builds bigger muscles.
19. How many times you lift a weight affects what your body gets better at: lifting heavy weights a few times builds strength, lifting lighter weights many times builds endurance, and doing a middle amount builds muscle size.
20. When you lift weights until you can't anymore, you build about the same muscle size no matter how many reps you do, but doing more reps makes you stronger than doing fewer reps.
Related Content
Claims (10)
When people who are already fit push themselves as hard as they can during weight training, it doesn't matter if they lift heavy weights for a few reps or lighter weights for many reps—both ways build muscle about the same.
Lifting lighter weights many times until you can't do any more builds as much muscle as lifting heavy weights a few times in people who already exercise regularly.
Lifting weights until you can't lift anymore makes muscles grow bigger no matter how heavy the weights are, but using heavier weights builds more strength than lighter ones.
When you lift weights until you can't anymore, you build about the same muscle size no matter how many reps you do, but doing more reps makes you stronger than doing fewer reps.
When untrained young men lift weights with different heavy loads but equal total work, their chest muscles grow about the same amount—around 10-11% bigger.
Studies (10)
Resistance exercise load does not determine training-mediated hypertrophic gains in young men.
DOI: 10.1152/japplphysiol.00307.2012
Neither load nor systemic hormones determine resistance training-mediated hypertrophy or strength gains in resistance-trained young men
DOI: 10.1152/japplphysiol.00154.2016
Low-Load Bench Press Training to Fatigue Results in Muscle Hypertrophy Similar to High-Load Bench Press Training
DOI: 10.4236/ijcm.2013.42022
Effects of Low- vs. High-Load Resistance Training on Muscle Strength and Hypertrophy in Well-Trained Men
DOI: 10.1519/jsc.0000000000000958
Early-phase muscular adaptations in response to slow-speed versus traditional resistance-training regimens
DOI: 10.1007/s00421-012-2339-3