Cardiovascular drift

• Definition


  a gradual increase in heart rate despite a consistent exercise intensity often associated with exercising in warm temperatures and/or for long periods of time.
• Causes

  • exercising in heat / for long periods of time
  • increased blood flow to skin for purposes of thermoregulation
  • fluid loss caused by sweating leading to dehydration
  • increased blood viscosity meaning decreased stroke volume and venous return
  • heart rate increases to maintain cardiac output
• Implications for athletes


  • train in hot conditions
  • provide time to acclimatise to heat
  • ensure they are hydrated and fluid levels are maintained during performance
  • manage exercise intensity to avoid temperature increasing too significantly
• Order

  heat - sweating - dehydration - increased blood viscosity - decreased venous return - decreased stroke volume - increased heart rate