Exercise Physiology – Week 10 Discussion

Vocabulary flashcards covering cardiac adaptations to training, exercise nutrition, fat-loss physiology, and heat illness.

Left Ventricular Hypertrophy (Athlete’s Heart)

Training-induced thickening of the left-ventricular wall that raises stroke volume, lowering heart rate at rest while preserving or enhancing cardiac output during exercise.

Left Ventricular Mass (LVM)

The total muscle mass of the left ventricle; increases with resistance training and is a marker of cardiac remodeling.

Relative Wall Thickness (RWT)

Ratio of ventricular wall thickness to internal cavity diameter; used to classify the pattern of cardiac hypertrophy.

Resting Bradycardia (in trained athletes)

A substantially lower resting heart rate caused by enlarged stroke volume and heightened parasympathetic (vagal) tone after endurance training.

Fat Oxidation Zone

Exercise intensity (usually moderate, ~60–70 % VO₂max) at which the body preferentially uses fat as fuel, making longer, moderate sessions effective for fat loss.

High-Intensity Interval Training (HIIT)

Short bursts of near-maximal effort alternated with rest; burns more calories per minute but relies more on carbohydrates and may yield less direct fat oxidation during the bout.

Pre-Exercise Nutrition

Carbohydrate-rich, low-fat meal with water taken ~2 h before activity to top up glycogen and prevent gastrointestinal discomfort.

Intra-Exercise Hydration

Small, frequent sips of water during exercise; add 50–100 kcal of carbohydrates every 30 min when workouts exceed 1 h or are very intense.

Post-Exercise Recovery Window

The 20–60 min period after exercise when muscles efficiently replenish glycogen and use protein for repair; ideal time for carbs + high-quality protein and fluids.

ACSM Nutrition Guideline

Recommendation that adequate food and fluid be consumed before, during, and after exercise to maintain blood glucose, optimize performance, and speed recovery.

Heat Exhaustion

A heat illness marked by heavy sweating, weakness, rapid pulse, and core temperature <40 °C; results from dehydration and peripheral vasodilation.

Heat Stroke

Life-threatening failure of thermoregulation with core temperature ≥40 °C plus CNS dysfunction (confusion, seizure, coma).

Positive Feedback Loop of Heat Stroke

Rising core temperature impairs sweating and heat loss, causing further temperature rise that damages hypothalamic control, accelerating the cycle until intervention or death.

Negative Feedback in Thermoregulation

Normal homeostatic mechanism where rising body temperature triggers sweating and vasodilation, which cool the body and restore set point.

Cross-Over Concept

Model describing how increasing exercise intensity shifts energy use from fats toward carbohydrates.

Concentric vs. Eccentric Hypertrophy

Weightlifting mainly produces concentric (wall-thickening) hypertrophy, whereas endurance exercise promotes eccentric (chamber-dilating) hypertrophy.