TSI Exercise Physiology & Kinesiology 5

Question 1

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

Accepted Answer

Increased plasma volume and earlier onset of sweating

Answer

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

Question 2

The primary physiological challenge of exercising at high altitude is:

Accepted Answer

Reduced partial pressure of oxygen

Answer

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

Question 3

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

Accepted Answer

Valsalva maneuver

Answer

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

Question 4

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

Accepted Answer

From smallest to largest

Answer

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

Question 5

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

Accepted Answer

Troponin

Answer

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

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