The bilateral deficit phenomenon (BLD) is defined as an inability of the neuromuscular system to generate maximal force when two homonymous limb operate simultaneously (bilateral contraction) with respect to the force developed when both limbs acts separately (unilateral contraction). From an applied perspective, movement patterns of bilateral homonymous limb are often developed during activities of day living, e.g. rising from a chair or opening a jar. The BLD can be considered an intrinsic property of the human neuromuscular system but could be enough important to constitute a performance-limiting factor for postmenopausal women that involves a degenerative loss of muscular strength. Therefore, a specific analysis of this phenomenon and its relation with activities of daily living, such as climbing a step and rising from a chair, is crucial for detecting variables of neuromuscular performance and develop strategies to minimize the loss of strength.

• 20 postmenopausal women unexperience in strength training or resistance training, without musculoskeletal, neurological diseases, and cardiovascular limiting-diseases were recruited.
• Maximum strength of lower limbs during leg-press exercise was measured for future analysis.
• The force-time curves were measured during climbing a step and rising from a chair.
• A fragility phenotype test was applied to the subjects to determine frailty phenotype classification, including; weight loss of greater than 10 lbs in the past 12 months, maximal handgrip strength, time to walk 15-ft at usual pace, self-reported leisure time physical activity, and self-reported exhaustion.
• The anthropometric measurements were performed by dual energy X-ray absorptiometry.

Inclusion Criteria:

• Postmenopausal women

Exclusion Criteria:

• Unexperienced in strength training or resistance training.
• Not musculoskeletal diseases.
• Not neurological diseases.
• Not cardiovascular limiting-diseases.
• Not fragility or pre-fragility phenotype.

Postmenopausal women not experienced in strength training or resistance, without musculoskeletal, neurological diseases, and cardiovascular limiting-factor.