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Summary

This study developed a fast, indirect method to estimate maximal strength (1 repetition maximum) in untrained individuals performing half-squats. The new model uses body weight load velocity to predict 1RM safely and effectively.

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Area of Science:

  • Exercise Physiology
  • Biomechanics
  • Sports Science

Background:

  • Accurate assessment of maximal strength, or 1 repetition maximum (1RM), is crucial for designing effective resistance training programs.
  • Traditional 1RM testing can be time-consuming and carries a risk of injury, particularly for untrained individuals.
  • Developing indirect, rapid methods for 1RM estimation is beneficial for practical application in training settings.

Purpose of the Study:

  • To develop and validate a rapid, indirect method for estimating the 1 repetition maximum (1RM) in untrained individuals during the half-squat exercise.
  • To establish a predictive model based on submaximal exercise performance.
  • To provide a safe and efficient alternative to traditional 1RM testing.

Main Methods:

  • One hundred and five physically active young subjects (87 men, 18 women) participated.
  • Subjects performed a submaximal test (3 repetitions at body weight load) and a 1-2 repetition maximum (RM) test during half-squat exercise on a Smith machine.
  • Barbell displacement velocity and power were recorded during the upward phase of the submaximal repetitions.

Main Results:

  • A predictive model was constructed using load and mean velocity (V(mean)) from the submaximal test.
  • The model demonstrated a statistically significant ability (F(exp) = 72.82; p ≤ 0.001) to estimate 1RM, with an accuracy of 58%.
  • A strong correlation was found between the mean velocity of a body weight load and the actual 1RM.

Conclusions:

  • The developed indirect method provides a safe and fast estimation of 1RM in the half-squat exercise for untrained individuals.
  • The formula (1RM = -61.93 + [121.92·V(mean)] + [1.74·load]) can be utilized by coaches and trainers.
  • This method offers valuable insights for individuals initiating resistance training programs, promoting safer and more informed strength development.