High-intensity Interval Training Improves Mitochondrial Function and Suppresses Thrombin Generation in Platelets...

Area of Science:

• Exercise Physiology
• Mitochondrial Biology
• Hemostasis

Background:

• Hypoxic exercise (HE) impairs platelet mitochondrial function and enhances thrombin generation (TG).
• The effects of different exercise intensities on these parameters post-hypoxia are not fully understood.
• Platelet mitochondrial dysfunction is linked to increased thrombotic risk.

Purpose of the Study:

• To investigate the impact of high-intensity interval training (HIT) versus moderate-intensity continuous training (MCT) on platelet mitochondrial function and TG after HE.
• To compare the efficacy of HIT and MCT in mitigating exercise-induced changes in platelet bioenergetics and coagulation.

Main Methods:

• Forty-five healthy sedentary males were randomized into HIT, MCT, or control (CTL) groups for a 6-week intervention.
• Participants underwent hypoxic exercise (HE) to assess platelet mitochondrial oxygen consumption rate (OCR), membrane potential (MP), oxidant burden (MOB), citrate synthase (CS), and succinate dehydrogenase (SDH) activity.
• Thrombin generation (TG) in platelet-rich plasma (PRP) was measured post-HE.

Main Results:

• HE reduced platelet mitochondrial function (ATP-linked OCR, reserve capacity, CS, SDH) and MP, while increasing MOB and TG.
• Six weeks of HIT significantly improved mitochondrial OCR capacity, enhanced CS and SDH activities, increased MP, and reduced MOB post-HE compared to MCT and CTL.
• HIT effectively suppressed the HE-induced increase in dynamic TG in PRP.

Conclusions:

• High-intensity interval training (HIT) enhances platelet mitochondrial bioenergetics following hypoxic exercise.
• HIT effectively suppresses hypoxia-induced increases in platelet thrombin generation.
• HIT demonstrates superior benefits over MCT in improving platelet function under hypoxic conditions.