Isokinetic Strength and Anaerobic Capacity

This study will investigate the relationship between anaerobic power classification and isokinetic lower-extremity muscle strength in recreationally active young adult males. Participants will be classified into three anaerobic power groups (low, moderate, and high) based on relative peak power (W/kg) obtained from the Wingate Anaerobic Test. This classification approach is intended to move beyond single-variable correlation analyses commonly reported in the literature and to enable meaningful group-based comparisons of muscle strength profiles.

A total of 80 male participants aged 22-30 years who engage in regular physical activity at least twice per week will be recruited. Individuals with a history of serious orthopedic injury within the past six months, cardiovascular or respiratory disease, or regular medication use will be excluded. Body composition parameters will be assessed using bioelectrical impedance analysis prior to performance testing.

Isokinetic knee extensor and flexor strength of the dominant leg will be evaluated using concentric contractions at an angular velocity of 60°/s. Peak torque and total work values will be recorded as primary isokinetic strength outcomes. Anaerobic performance will be assessed on a separate day using a 30-second Wingate Anaerobic Test performed on a cycle ergometer, during which participants will be verbally encouraged to exert maximal effort throughout the test. Relative peak power, mean power, and fatigue index values will be obtained.

Participants will be grouped according to median-based classification of relative peak power values to facilitate comparison among anaerobic power levels in a sample of limited size. Differences in isokinetic strength parameters between groups will be analyzed using one-way analysis of variance or non-parametric equivalents when appropriate. Associations between Wingate-derived anaerobic parameters and isokinetic strength measures will also be examined using correlation analyses.

The results of this study are expected to clarify whether individuals with higher anaerobic power levels demonstrate superior isokinetic knee extensor and flexor strength profiles. The findings may contribute to a better understanding of the interaction between anaerobic performance capacity and lower-extremity muscle strength, with potential implications for performance profiling, training program design, and exercise-based rehabilitation strategies in recreationally active populations.

Inclusion criteria

• Male participants aged between 20 and 30 years

• Moderately physically active individuals, as defined by the International Physical Activity Questionnaire (IPAQ)
• Apparently healthy, with no known neurological, vestibular, or musculoskeletal disorders affecting balance
• Ability to stand independently and complete balance assessments
• Willingness to participate and provide written informed consent

Exclusion criteria

• History of lower-limb, spine, or pelvic injury or surgery within the past 6 months

• Presence of acute or chronic pain affecting posture or balance
• Diagnosed neurological, vestibular, or balance disorders
• Use of medications or substances that may affect neuromuscular function or postural control
• Participation in another clinical or observational study within the past 3 months