Oral Contraceptive Use Dampens Physiological Adaptations to Sprint Interval Training

Area of Science:

• Exercise Physiology
• Sports Science
• Endocrinology

Background:

• Oral contraceptive (OC) use is known to reduce peak aerobic capacity (V˙O2peak).
• The impact of OC use on physiological adaptations to exercise training remains unclear.
• Understanding these effects is crucial for interpreting training responses in women.

Purpose of the Study:

• To investigate the influence of oral contraceptive use on peak performance (peak power output [PPO]) and physiological adaptations (V˙O2peak, peak cardiac output [Q˙peak]).
• To examine these effects after a period of sprint interval training (SIT) in recreationally active women.

Main Methods:

• 12 sessions of SIT were administered over an unspecified period.
• Participants included women using OCs (n=25) and those with natural menstrual cycles (MC; n=16).
• V˙O2peak, PPO, and Q˙peak were assessed before, immediately after, and 4 weeks after SIT.

Main Results:

• Both groups improved V˙O2peak and Q˙peak after SIT, but the MC group showed significantly greater improvements.
• Peak power output (PPO) increased similarly in both groups.
• While parameters decreased 4 weeks post-training, OC users exhibited more sustained V˙O2peak improvements.

Conclusions:

• Sprint interval training enhances peak exercise responses in recreationally active women.
• Oral contraceptive use attenuates adaptations in V˙O2peak and Q˙peak.
• OC use may alter the temporal profile of training adaptations, necessitating consideration in exercise research and practice.