Until recently, there weren’t any controlled studies examining which training variables impact lean mass retention during intentional weight loss. However, that trend appears to be changing. Earlier this year, Roth and colleagues published a review of the preliminary data on the topic (discussed here; 2). A couple of months ago, Carlson and colleagues published a study examining whether training with higher versus lower loads led to better body composition outcomes while dieting (discussed here; 3). Now, a new study by Roth and colleagues (1) examines the impact of training volume: does a higher training volume improve muscle retention while dieting?
38 resistance-trained, relatively lean males were randomized into two groups with different training volumes. Subject characteristics can be seen in Table 1.
Both groups completed a seven-week training and diet intervention. During the first week, subjects were instructed to consume 45kcal per kg of body mass (which was assumed to be the subjects’ maintenance energy requirement) while completing a moderate-volume training program. During weeks 2-7, subjects were instructed to consume 30kcal per kg of body mass (which was intended to induce a moderate energy deficit). One group of subjects kept training with a moderate volume, while the other group switched to a higher-volume program. The moderate-volume program consisted of 1-3 sets of various exercises, while the higher-volume program consisted of 3-5 sets of the same exercises (all exercises were performed for sets of 10 reps). Both programs used an upper-lower split, with two upper-body days and two lower-body days per week. Training loads were progressed using reps in reserve – training loads were reduced when a subject had 0 reps in reserve at the end of a set, and increased when a subject had more than 3 reps in reserve at the end of a set. More details about the programs can be seen in Table 2.
Before and after the 6-week hypocaloric intervention period, rectus femoris thickness was assessed via ultrasound, body composition was assessed via multi-frequency bioelectrical impedance analysis (BIA), and muscle contractility was assessed via tensiomyography (TMG) and mechanomyography (MMG). Furthermore, subjective sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), and mood states were assessed using the Profile of Mood States (POMS) questionnaire.
We’ve discussed TMG in MASS Research Review before – if you’re unfamiliar with this technique, you can look back at this prior article that describes how it works. MMG is sort of like electromyography (EMG), which most MASS readers are likely familiar with. While EMG uses electrodes to measure electrical activity within the muscles as a proxy for muscle activation, MMG uses acoustic sensors to measure vibrations within the muscles as a proxy for muscle activation. However, TMG and MMG outcomes didn’t differ between groups in this study (and this is a research brief, after all), so I’m not going to discuss those techniques in detail.
Overall, moderate- and higher-volume training produced similar results across the board. Changes in total body mass, lean mass, and body fat percentage were similar in both groups. Neither group experienced a meaningful change in rectus femoris thickness (Figure 1).
Assessments of muscle contractility didn’t significantly change over time, or differ between groups. Both groups were able to slightly increase training loads over time for most exercises. Finally, sleep quality and mood states also didn’t significantly change over time, or differ between groups (Table 3).
Much like the prior article I discussed in MASS (examining the impact of training with higher versus lower loads during an energy deficit; 3), this study largely found that training volume didn’t meaningfully impact body composition outcomes when training in a deficit (1). However, there are a couple of caveats to keep in mind.
First, subjects were relatively lean (a subject would be excluded if they exceeded 25% body fat), but they weren’t super lean. They started at ~18.5-19% body fat, and ended at ~17.5% body fat. Furthermore, they were in a pretty modest energy deficit, averaging 1.725kg of weight loss over 6 weeks (about 0.29kg per week). So, it’s entirely possible that training volume would have a large impact on body composition outcomes if the subjects were considerably leaner, or employing a considerably larger energy deficit.
When people argue in favor of relatively high training volumes in an energy deficit, their argument generally presupposes circumstances when large losses of lean mass are likely (i.e., when someone is already very lean or in a very large energy deficit). Under these circumstances, it’s argued that a higher training volume will be needed to provide an adequate stimulus for maintaining muscle mass. Similarly, when people argue in favor of lower training volumes in an energy deficit, their argument generally presupposes circumstances where recovery from training will be impaired (i.e., when someone is already very lean or in a very large energy deficit). Under these circumstances, it’s argued that a lower training volume is required, because lifters will be unable to adequately recover from higher-volume training.
Ultimately, the present study provides us with some great preliminary evidence suggesting that differing levels of training volume won’t lead to night-and-day differences in body composition when dieting, but I suspect it will do little to shift change the opinions of people who are all-in on the higher- or lower-volume side of the debate. The subjects weren’t lean enough or cutting fast enough to anticipate a large loss of lean mass, and their sleep, mood state, and training load data suggest that recovery from training wasn’t much of an issue.
The second caveat to keep in mind is that the training volume didn’t differ that much between groups. One group did five sets of most exercises, and one group did three sets of most exercises. We only have direct hypertrophy measures for the rectus femoris, which was targeted with 12 total sets per week in one group, and 20 total sets per week in the other group. Functionally, I’d consider both of these set totals to be near the lower and upper end of the “moderate volume” range. So, it’s certainly possible (potentially even likely) that we’d observe different results if one group did 5 sets of quad training per week, and one group did 30 sets. Basically, we shouldn’t overlook the actual details of the study: the study found that training volume didn’t influence body composition results through the (relatively small) range of volume that was directly studied. We shouldn’t interpret these results to mean that all plausible training volumes (which span a much wider range) produce similar results.
While the present study doesn’t answer every question we might have about the impact of training volume when dieting, it does still provide insights that are relevant to a lot of dieters. It’s fun to theorycraft about how to optimize results during extreme circumstances (very large energy deficits, or when pursuing extreme levels of leanness), but most weight loss attempts more closely resemble the details of the present study: people who aren’t already super lean, aiming to lose weight at a modest rate. If that describes you, this study suggests that you probably don’t need to be super concerned about your training volume – doing a couple extra sets probably isn’t going to lead to dramatically better body composition outcomes, nor will it rapidly lead to overtraining and difficulty recovering. The general volume recommendations that apply when you’re in neutral energy balance likely still apply when you’re in a modest energy deficit.
Note: This article was published in partnership with MASS Research Review. Full versions of Research Spotlight breakdowns are originally published in MASS Research Review. Subscribe to MASS to get a monthly publication with breakdowns of recent exercise and nutrition studies.
- Roth C, Schwiete C, Happ K, Rettenmaier L, Schoenfeld BJ, Behringer M. Resistance training volume does not influence lean mass preservation during energy restriction in trained males. Scand J Med Sci Sports. 2022 Sep 17. doi: 10.1111/sms.14237. Epub ahead of print. PMID: 36114738.
- Roth C, Schoenfeld BJ, Behringer M. Lean mass sparing in resistance-trained athletes during caloric restriction: the role of resistance training volume. Eur J Appl Physiol. 2022 May;122(5):1129-1151. doi: 10.1007/s00421-022-04896-5. Epub 2022 Feb 11. PMID: 35146569; PMCID: PMC9012799.
- Carlson L, Gschneidner D, Steele J, Fisher JP. The Effects of Training Load During Dietary Intervention Upon Fat Loss: A Randomized Crossover Trial. Res Q Exerc Sport. 2022 Aug 23:1-11. doi: 10.1080/02701367.2022.2097625. Epub ahead of print. PMID: 35998256.