Weightlifters bulk to build muscle.

Yet, many fall short of their muscle-building goals despite maintaining a calorie surplus.

There are reams of reasons this can happen. Often, however, it boils down to sub-optimal training.

How should you work out while bulking to sidestep this prevalent pitfall?

A recent study funded by Legion and conducted by a group of esteemed fitness scientists, including  Eric Helms and James Kreiger, offers some valuable insights.

The Study

The study aimed to pinpoint the perfect calorie surplus for maximizing muscle growth and minimizing fat gain.

The researchers split 17 seasoned weightlifters into three groups:

  • Group 1 (maintenance group) ate maintenance calories.
  • Group 2 (small-surplus group) ate in a 5% calorie surplus (5% more than their TDEE).
  • Group 3 (large-surplus group) ate in a 15% calorie surplus (15% more than their TDEE).

Over the following 8 weeks, the dieters ate 3-to-5 meals spread evenly throughout the day. They also consumed a minimum of 0.8 grams of protein per pound of body weight daily and got a minimum of 20% and 40% of daily calories from fat and carbs, respectively.

Additionally, the dieters did three full-body workouts weekly. Their workouts were periodized, prioritized progressive overload, and included the squat, bench press, lat pulldown, one-arm dumbbell row, shoulder press, lateral raise, and various types of biceps curls.

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The Results

Unfortunately, the dieters didn’t adhere to their assigned diets closely enough, making it impossible to draw any conclusions about the ideal calorie surplus size.

Despite this setback, the study’s secondary findings relating to muscle growth provided valuable insights into effective bulking training techniques.

They showed that all the dieters gained next to no muscle during the study. The only exception was the biceps, which grew significantly in both surplus groups.

There are two likely reasons for this:

  1. The dieters trained their biceps with more volume (sets) than every other muscle. For example, they trained their quads with 9 weekly sets of squats and triceps with 15 weekly sets of bench and shoulder press. In contrast, they did 18 weekly sets of biceps training using a mixture of compound and isolation exercises
  2. The scientists instructed the dieters to perform most sets of the squat and bench press far from failure, whereas they encouraged the dieters to take all exercises involving the biceps to “volitional failure”—the point at which they could no longer perform the exercise with proper form.

In essence, the dieters trained their quads with relatively low volume at a relatively low intensity; their triceps with moderate volume, mostly at a low intensity; and their biceps with high volume and intensity. 

How to Maximize Muscle Growth While Bulking

This study highlights three areas experienced weightlifters should focus on to maximize muscle growth while bulking.

1. Do the right amount of volume.

These findings build on earlier research showing that experienced weightlifters should train with higher volumes to continue gaining muscle and strength effectively.

Previous studies suggest 15-to-20 weekly sets per major muscle group is the optimal range. These results agree but suggest leaning toward the higher end may be more beneficial. 

According to the authors, aiming for the upper end is especially important while bulking since doing so potentially encourages your body to use surplus calories to build muscle rather than store them as fat.

2. Train with enough intensity. 

The results provide evidence that ending most of your sets within a rep or two of failure is likely better for muscle gain than training further from failure. 

While most weightlifters feel they’re busting a gut in the gym, research shows many aren’t training hard enough. For instance, a study conducted by researchers at Solent University found that regular gym-goers generally train 6-to-7 reps shy of failure despite believing they’re training much harder. 

To avoid sandbagging, ask yourself at the end of each set, “If I absolutely had to, how many more reps could I have gotten with good form?” If the answer is more than two, increase the weight or reps to make your next set more challenging.

3. Include isolation exercises. 

The findings underline the advantage of including both compound and isolation exercises in your program.

Although it counters many “minimalist” training perspectives, ample evidence shows that doing both compound and isolation exercises produces more balanced muscle growth than doing just 2 or 3 compound exercises.

That’s why I recommend dedicating approximately 80% of your training time to compound exercises and the remaining 20% to isolation exercises.

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A key challenge in real-world diet research is ensuring participants adhere to the diet and report their eating accurately.

This challenge greatly skewed this study’s data, making the results inconclusive.

The study wasn’t in vain, though.

Its secondary findings highlighted some important points about training while bulking that many experienced trainees overlook. Specifically, they showed that for experienced weightlifters to maximize muscle growth while bulking, they should:

  1. Aim for close to 20 weekly sets per major muscle group
  2. Push each set to within 1-to-2 reps of failure
  3. Perform a combination of compound and isolation exercises

If you like training tips like these and want even more advice about building muscle as an experienced weightlifter, check out my fitness book Beyond Bigger Leaner Stronger.