Does Exercise Variation for the Same Muscle Group Enhance Muscular Adaptations?

Brandon Hyatt, MS, CSCS

Dec. 04, 2024

Many individuals incorporate diverse exercises into their training programs to optimize muscular adaptations, while others adhere to a consistent set of movements. However, the comparative benefits of frequent variation versus routine consistency remain an open question. This article examines the effects of exercise variation on muscle hypertrophy and strength.

How Is Exercise Variation Achieved?

Of the tens of thousands of resistance training exercises available, most can be categorized into a limited set of movement patterns or muscle group “splits.” Common movement patterns include:

• Push

• Pull

• Squat

• Hinge

• Lunge

• Rotate

• Carry/gait

From this framework, nearly unlimited exercise variation can be derived. Variation is achieved through several mechanisms, including:

• Movement type: Multi-joint (e.g., dumbbell chest press) vs. single-joint (e.g., cable chest fly)

• Limb involvement: Bilateral (e.g., barbell row) vs. unilateral (e.g., single-arm dumbbell row)

• Implement: Machines, free weights, bands, or bodyweight (e.g., machine vs. barbell hip thrust)

• Kinetic chain: Closed (e.g., pull-ups) vs. open (e.g., lat pulldowns)

• Joint angle: Incline vs. decline bench press

• Positioning: Grip (closed vs. open) or foot stance (wide vs. split)

• Range of motion (ROM): Partial (long-length bicep curls) vs. full ROM

• Tempo: Fast, slow, paused, or quarter-rep execution

Why Is Exercise Variation Important?

Exercise variation enables individuals to train within their functional capacity—regardless of skill level, injury history, or chronic conditions—by replacing inaccessible exercises with functionally similar alternatives.

At the hypertrophy level, research demonstrates that distinct exercise variations induce regional muscular adaptations (e.g., distal biceps hypertrophy) (6, 8). Even non-trivial exercise differences (beyond minor modifications) elicit regional adaptations (2). This raises a critical question: Does variation confer unique benefits, or is it redundant? (5).

The principle of training specificity dictates that improvements are specific to the training stimulus. Does variation contradict this? Related accessory exercises have shown strength transfer effects (5), suggesting a tolerable range of variation that aligns with specificity.

Research Insights on Exercise Variation

Moderate exercise variation appears to enhance hypertrophy and strength, whereas excessive, random variation may compromise gains (5). One study found superior strength adaptations with varied routines compared to fixed programs (4), though two others reported no differences (1, 7).

Frequent rotation (e.g., weekly) can induce prolonged fatigue due to novel stimuli, delaying recovery. Excessive variation also reduces volume for specific exercises, lowering load capacity (3). Conceptually, the impact of variation on muscle growth follows an inverted U-curve: benefits increase up to a threshold, beyond which negative effects emerge (5, Nunes).

A study of trained males comparing consistent vs. varied exercises (equated weekly volume) found both groups improved dynamic strength. However, the consistent group showed slightly higher isometric strength and lifted greater overall loads (3).

Conclusion

Should you vary or maintain exercises for optimal strength and hypertrophy? As long as variation aligns with your training objectives, exercise variations are acceptable—and so is consistency.

For recreational lifters, adherence to core principles (volume, rep ranges, intensity) outweighs exercise variation. For athletes or competitive lifters, variation may offer advantages like targeted regional hypertrophy or maximal volume-load.

Sources

1. Baz-Valle E, Schoenfeld BJ, Torres-Unda J, Santos-Concejero J, Balsalobre-Fernandez C. The effects of exercise variation in muscle thickness, maximal strength and motivation in resistance trained men. PLoS One. 2019;14(12):e0226989.

2. Brandão L, et al. "Varying the order of combinations of single-and multi-joint exercises differentially affects resistance training adaptations." The Journal of Strength & Conditioning Research. 2020;34(5):1254–1263.

3. Costa BDV, Kassiano W, Nunes JP, Kunevaliki G, Castro-E-Souza P, Sugihara Junior P, Fernandes RR, Cyrino ES, Fortes LS. Does Varying Resistance Exercises for the Same Muscle Group Promote Greater Strength Gains? J Strength Cond Res. 2022 Nov 1;36(11):3032–3039. doi: 10.1519/JSC.0000000000004042.

4. Fonseca RM, Roschel H, Tricoli V, et al. Changes in exercises are more effective than in loading schemes to improve muscle strength. J Strength Cond Res. 2014;28(11):3085–3092.

5. Kassiano W, Nunes JP, Costa B, Ribeiro AS, Schoenfeld BJ, Cyrino ES. Does Varying Resistance Exercises Promote Superior Muscle Hypertrophy and Strength Gains? A Systematic Review. J Strength Cond Res. 2022 Jun 1;36(6):1753–1762. doi: 10.1519/JSC.0000000000004258.

6. Nunes JP, Costa BDV, Kassiano W, Kunevaliki G, Castro-E-Souza P, Rodacki ALF, Fortes LS, Cyrino ES. Different Foot Positioning During Calf Training to Induce Portion-Specific Gastrocnemius Muscle Hypertrophy. J Strength Cond Res. 2020 Aug;34(8):2347–2351. doi: 10.1519/JSC.0000000000003674.

7. Rauch JT, Ugrinowitsch C, Barakat CI, et al. Auto-regulated exercise selection training regimen produces small increases in lean body mass and maximal strength adaptations in strength-trained individuals. J Strength Cond Res. 2020;34(4):1133–1140.

8. Sato S, et al. "Elbow joint angles in elbow flexor unilateral resistance exercise training determine its effects on muscle strength and thickness of trained and non-trained arms." Frontiers in Physiology. 2021;12:734509.