Determining the One Repetition Maximum in the Ballistic Bench Press Exercise.

Area of Science:

• Sports Science
• Biomechanics
• Strength and Conditioning

Background:

• Determining the propulsive phase in resistance exercises is crucial for optimizing training.
• The bench press (BP) is a common measure of upper body strength.
• Understanding the load at which the bench press becomes purely propulsive is key for performance analysis.

Purpose of the Study:

• To identify the relative load (% of one repetition maximum [1RM]) where the bench press concentric action becomes entirely propulsive.
• To investigate if this propulsive load threshold differs between athletes of varying strength levels.

Main Methods:

• Twenty-eight professional athletes (boxers, MMA fighters, rugby players) underwent progressive loading to determine their BP-1RM.
• Athletes were categorized into 'low' and 'high' relative strength groups.
• Propulsive velocity and maximal braking load during the BP were analyzed.

Main Results:

• No significant differences were found between strength groups in mean propulsive velocity at 1RM or maximal braking load.
• The concentric action in the bench press exercise was found to be 100% propulsive at 80% of 1RM.
• This 80% 1RM threshold for propulsive action was consistent across all participants, irrespective of their strength level.

Conclusions:

• The 80% 1RM mark in the bench press represents a reliable point where the concentric phase is fully propulsive.
• This finding is independent of the athlete's overall strength level.
• The 80% BP-1RM can serve as a practical reference for assessing the one repetition maximum in the bench press throw.