Exercise Physiology & Kinesiology Flashcards

Which adaptation occurs during heat acclimatization over roughly 10-14 days?

Answer: Increased plasma volume and earlier onset of sweating

Acclimatization expands plasma volume, starts sweating sooner, and conserves sodium to improve heat tolerance.

The primary physiological challenge of exercising at high altitude is:

Answer: Reduced partial pressure of oxygen

Oxygen stays about 20.9% of air, but lower barometric pressure reduces its partial pressure and arterial saturation.

Holding the breath against a closed glottis while lifting heavy loads is called the:

Answer: Valsalva maneuver

The Valsalva maneuver raises intra-abdominal pressure but can sharply spike blood pressure.

According to Henneman's size principle, motor units are recruited in what order?

Answer: From smallest to largest

Small, low-threshold motor units are recruited first, with larger units added as force demands increase.

In the sliding filament theory, calcium initiates contraction by binding to:

Answer: Troponin

Calcium binding to troponin shifts tropomyosin, exposing actin binding sites for myosin cross-bridges.

An endurance athlete who drinks large amounts of plain water during a long event is at increased risk of:

Answer: Exertional hyponatremia

Excess water intake dilutes blood sodium, which can cause dangerous exertional hyponatremia.

On the original Borg Rating of Perceived Exertion scale, what is the numerical range?

Answer: 6-20

The original Borg scale runs from 6 to 20, roughly corresponding to heart rate divided by 10.