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Which Training Technique is better for Building Muscles?


Clinical trial finds that muscle building can be achieved by adding reps or by adding weight

A clinical trial compared the effects of two resistance training programs: (1) increasing load while keeping repetition range constant vs (2) increasing repetitions while keeping load constant, on the lower body muscles.

Resistance training is a powerful tool to aid in developing muscle size, strength, endurance, power, and many other positive physiological outcomes. While the role of resistance training in muscle growth and strength is well established, the mechanism of progressive overload to maintain an adequate stimulus to match the adaptive capacity of the muscles has always been a source of controversy.

What is Progressive Overload?

In simple terms, progressive overload is a principle that suggests to get stronger and build muscles, you need to gradually increase the stress on your muscles over time.

Traditionally, this involves either adding more weight to your exercises or increasing the number of repetitions. However, clinical data on the comparison between these two methods is limited.

Clinical Trial

The clinical trial evaluated the effects of the two methods of progressive overloading on muscle hypertrophy, strength, and endurance. It involved 43 participants who were split into two groups. The first group focused on increasing the load they lifted, while the second group concentrated on increasing the number of repetitions performed. Both groups followed an 8-week training program that consisted of four sets of four lower body exercises (back squat, leg extension, straight-leg calf raise, and seated calf raise) twice per week. Their muscle adaptations were measured before and after the study.

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The results of the clinical trial were unexpected. The group that focused on increasing the load they lifted experienced significant muscle growth, as anticipated. However, the group that focused on increasing the number of repetitions also demonstrated notable muscle gains, even though they did not lift heavier weights. This means that progression in repetitions can be an effective method to build muscles, even without increasing the load you lift.

Implications for Strength Training

These findings have significant implications for strength training enthusiasts. It suggests that individuals who struggle with lifting heavy weights may still achieve muscle growth by focusing on increasing the number of repetitions. This alternative approach can help people vary their workouts and provide them with more flexibility in their training routines.


The clinical trial sheds light on the fascinating world of strength training. It shows that progressive overload, a fundamental principle in building muscles, can be achieved not only by increasing the weight you lift but also by increasing the number of repetitions. So, whether you prefer to lift heavy or perform more repetitions, remember that both methods may lead to muscle growth and strength gains.

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This content is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of such advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. CenTrial Data Ltd. does not take responsibility for possible health consequences of any person or persons reading or following the information in this educational content. Treatments and clinical trials mentioned may not be appropriate or available for all trial participants. Outcomes from treatments and clinical trials may vary from person to person. Consult with your doctor as to whether a clinical trial is a suitable option for your condition. Assistance from generative AI tools may have been used in writing this article.