Full Body Workouts: New Study Shows Lower Reps Training Leads to Greater Muscle Gains Summary
- The study shows that full-body workouts using heavier weights with fewer repetitions (i.e., 10 reps) result in greater muscle gains, especially in the upper body, compared to lighter weights with more repetitions (i.e., 30 reps).
- The participants who performed 10 reps resistance training saw more substantial improvements in both upper and lower body strength, with a 10% greater increase in lower limb strength compared to the 30 reps group.
- While high-load training is better for building strength and muscle mass, both methods were equally effective in improving agility and muscle endurance, making either option valuable depending on fitness goals.
Are Full Body Workouts as Good as Split Routines for Gaining Muscle?
When it comes to building muscle, the debate surrounding the effectiveness of full-body workouts versus split routines for muscle gain has garnered significant attention in the fitness community. While traditional wisdom often favors split routines, recent research indicates that full-body workouts can be equally effective for certain populations and training goals. 1-3 When it comes to full-body workouts, many people with limited train time are looking for the most effective way to build muscle and strength in just two to three sessions per week.
For years, the common belief was that if the training volume is the same, the weight doesn’t matter – you’d get the same results whether it was a full body or split routine.4 However, a new study has challenged that idea. The study, titled “Superiority of High-Load vs. Low-Load Resistance Training in Military Cadets,” conducted by Sjur F. Øfsteng and colleagues and published in the Journal of Strength and Conditioning Research, suggests that heavier weights with fewer reps (around 10 repetitions) lead to greater muscle mass gains compared to lighter weights with more reps (up to 30 repetitions).3
Overview of the Full Body Workout Study Protocol
This study focused on 27 cadets from the Norwegian Defense Cyber Academy. The participants, moderately trained individuals aged around 20, were split into two groups: a heavy-weight group and a high-rep group. Both groups followed a full-body workout routine for 22 weeks, performing exercises like squats, bench presses, leg presses, and bicep curls. The heavy weights group used weights that allowed them to complete up to 10 repetitions per set (10RM), while the high repetitions group worked with lighter weights that allowed for up to 30 repetitions per set (30RM).
The workouts were performed twice weekly for the first 10 weeks, then increased to three sessions every other week for the remaining 9 weeks. Each session consisted of seven different exercises targeting the whole body, and participants were required to lift until they couldn’t complete another rep with good form. In addition to their workouts, both groups consumed a protein supplement post-workout to support muscle growth.
The study was designed to compare how the different load conditions affected muscle mass, strength, power, agility, and endurance. Notably, the diet and outside physical activity of the cadets were also monitored to ensure that the differences in results were due to the training methods, not other factors.
Results
Muscle Mass Gains for Full Body Workouts: The group that lifted heavy weights for the full body workout experienced significantly greater gains in upper-body muscle mass than the group that performed high repetitions. The arms of the heavy weights group showed a 5.2% increase in lean muscle mass, while the high repetitions group saw much smaller improvements.
Strength Improvements: Strength gains were more pronounced in the heavy weights group. For example, the bicep curl strength of the heavy weights group increased by 9.1%, while bench press strength improved by 7.8%. These results were much higher than those achieved by the high repetitions group.
Lower Body Gains: Both groups saw improvements in lower-body strength and muscle mass, but the heavy weights group still achieved about 10% greater gains in lower limb strength than the high repetitions group.
Agility and Endurance: Interestingly, both training methods resulted in similar improvements in agility and endurance, suggesting that the weight load may not be as important for these aspects of fitness.
Discussion
The results of the study make it clear that when performing full-body workouts, lifting heavy weights with fewer repetitions is the best approach for increasing muscle mass and strength. In particular, the heavy weights group saw significantly better results in upper-body exercises like bicep curls and bench presses compared to the high repetitions group One key reason could be that lifting heavier weights places more mechanical tension on the muscles, a critical factor for muscle hypertrophy. While both heavy and light loads can build strength, heavy loads are more effective for increasing muscle size and strength over time, particularly in full-body workouts.5,6
The differences in lower-body gains were less pronounced because many participants were already engaged in activities like running and marching, which likely contributed to leg development. Therefore, their legs may have been less responsive to the additional stimulus provided by heavy weights compared to the upper body.7 In the ongoing debate between full-body routines and split routines, evidence shows that full-body workouts may lead to faster recovery and more frequent training of each muscle group than split routines. Both split and full-body routines can yield similar results if the volume is equal, but full-body workouts offer the advantage of reduced “junk volume,” leading to more efficient training.8
Practical Applications for Full Body Training
For anyone aiming to get stronger and build muscle through full-body workouts, this study offers some practical takeaways:
Heavy Weights for Muscle Growth: If your goal is to build muscle and get stronger, focus on lifting heavier weights for fewer reps. The results from this study clearly show that working in the 10-rep range leads to greater gains in muscle mass, especially for the upper body.
Lower Body Considerations: While both training methods will improve lower body strength if you’re also engaging in activities that target the legs (like running or hiking), you may not need to rely solely on heavy loads to see gains.
Consistency is Key: The study spanned 22 weeks, showing that long-term commitment to a program is crucial. Whether using light or heavy weights, consistent, full-body workouts are essential for strength and muscle gains.
Full-Body Workouts for Busy Schedules: For those who can only train two or three times per week, full-body workouts incorporating heavier weights will give you the most bang for your buck. This study shows that these sessions target all major muscle groups and are highly effective when using heavier weights.
References
1 Bartolomei, S. et al. A Comparison Between Total Body and Split Routine Resistance Training Programs in Trained Men. The Journal of Strength & Conditioning Research 35 (2021).
2 Evangelista, A. L. et al. Split or Full-Body Workout Routine: Which Is Best to Increase Muscle Strength and Hypertrophy? Einstein (São Paulo) 19 (2021). https://doi.org/10.31744/einstein_journal/2021ao5781
3 Franco, C. M. C., Carneiro, M. A. S., Sousa, J. F. R. d., Gomes, G. K. & Orsatti, F. L. Influence of High- And Low-Frequency Resistance Training on Lean Body Mass and Muscle Strength Gains in Untrained Men. The Journal of Strength and Conditioning Research 35, 2089-2094 (2021). https://doi.org/10.1519/jsc.0000000000003145
4 Ramos-Campo, D. J., Benito-Peinado, P. J., Andreu-Caravaca, L., Rojo-Tirado, M. A. & Rubio-Arias, J. Á. Efficacy of Split Versus Full-Body Resistance Training on Strength and Muscle Growth: A Systematic Review With Meta-Analysis. The Journal of Strength and Conditioning Research 38, 1330-1340 (2024). https://doi.org/10.1519/jsc.0000000000004774
5 Campos, G. E. et al. Muscular adaptations in response to three different resistance-training regimens: specificity of repetition maximum training zones. Eur J Appl Physiol 88, 50-60 (2002). https://doi.org/10.1007/s00421-002-0681-6
6 Mitchell, C. J. et al. Resistance exercise load does not determine training-mediated hypertrophic gains in young men. J Appl Physiol (1985) 113, 71-77 (2012). https://doi.org/10.1152/japplphysiol.00307.2012
7 Lasevicius, T. et al. Muscle Failure Promotes Greater Muscle Hypertrophy in Low-Load but Not in High-Load Resistance Training. J Strength Cond Res 36, 346-351 (2022). https://doi.org/10.1519/jsc.0000000000003454
8 Pedersen, H. et al. A randomized trial on the efficacy of split-body versus full-body resistance training in non-resistance trained women. BMC Sports Science, Medicine and Rehabilitation 14, 87 (2022). https://doi.org/10.1186/s13102-022-00481-7
