Training specificity performing single-joint vs. multi-joint resistance exercises among physically active females: A...

Area of Science:

• Exercise Physiology
• Sports Science
• Biomechanics

Background:

• Lower limb resistance training can involve single-joint or multi-joint exercises.
• Understanding the specific effects and transferability of strength gains from different training modalities is crucial for optimizing training programs.

Purpose of the Study:

• To compare the effects of multi-joint (leg press) versus single-joint (leg extension, kickback) training on dynamic and isometric lower limb strength.
• To investigate the transferability of dynamic strength gains between different lower limb exercises following these training modalities.

Main Methods:

• Fifty-three physically active women were randomized into a multi-joint (MJ) training group, a single-joint (SJ) training group, or a control (CON) group.
• Training involved 18 supervised sessions over 8 weeks.
• Pre- and post-training assessments included 6-repetition maximum (RM) and maximal voluntary isometric contraction for leg press, leg extension, and kickback, along with quadriceps electromyography.

Main Results:

• Both MJ and SJ training groups showed significant improvements in dynamic and isometric strength across all tested exercises compared to the CON group.
• The SJ group exhibited greater improvements in leg extension and kickback 6RM compared to leg press.
• The MJ group showed comparable improvements in leg press and leg extension strength, with greater leg press strength gains than kickback.

Conclusions:

• Training specific lower limb exercises, whether single-joint or multi-joint, leads to the greatest improvements in dynamic strength for those particular exercises.
• Both multi-joint and single-joint training approaches can result in strength improvements across a range of lower limb exercises, indicating some degree of strength transferability.
• The choice between single-joint and multi-joint training may depend on the specific strength goals for individual exercises.