Physiological Performance Determinants of a 22-km Handbiking Time Trial

Area of Science:

• Sports Science
• Exercise Physiology
• Rehabilitation Science

Background:

• Handbiking (HB) is a prominent adaptive sport for individuals with paraplegia.
• Understanding the physiological underpinnings of HB performance is crucial for training optimization and athletic development.
• High-level paraplegic athletes require specific physiological assessments to enhance their competitive capabilities.

Purpose of the Study:

• To identify key physiological determinants influencing partial lap and overall 22-km handbiking time trial performance.
• To correlate physiological variables with race velocity and metabolic cost in elite paraplegic handbikers.
• To elucidate the relationship between oxygen uptake, power output, and handbiking race outcomes.

Main Methods:

• Seven male athletes with high paraplegia (T2-T8 spinal cord injury) underwent laboratory maximal incremental testing.
• Cardiorespiratory and mechanical parameters including oxygen uptake (VO2), respiratory-exchange ratio (RER), and power output (PO) were monitored.
• Athletes completed a simulated 22-km, 4-lap handbiking time trial, with metabolic cost (C) and %VO2peak calculated.

Main Results:

• Significant positive correlations were found between VO2peak, POpeak, VO2VT1, VO2VT2, and race performance (velocity).
• Metabolic cost (C) across laps 2, 3, and 4 also showed significant positive correlations with performance.
• %VO2peak demonstrated a strong, significant relationship with mean race velocity (v) within subjects (r = .68, P < .001).

Conclusions:

• Peak oxygen uptake (VO2peak) and peak power output (POpeak) are critical physiological determinants for handbiking time trial success.
• Ventilatory thresholds (VO2VT1, VO2VT2) and metabolic cost (C) are important physiological factors impacting performance.
• %VO2peak and C are significant predictors of handbiking race velocity in athletes with high paraplegia.