ADAPTIVE RESISTANCE: The process by which muscles increase strength and endurance in response to progressive training stress.
AEROBIC EXERCISE: Physical activity that relies on large muscle groups, steady oxygen consumption, and increased heart rate.
ANABOLIC STATE: A physiological condition where muscle building and tissue repair exceed breakdown, usually supported by training, nutrition, and recovery.
ANAEROBIC EXERCISE: Short-duration, high-intensity exercise that relies on energy sources stored in the muscles, not oxygen.
ATP (ADENOSINE TRIPHOSPHATE): The primary energy currency of the body, used to fuel muscle contractions during exercise.
BALANCE: The ability to maintain the body’s center of gravity over its base of support, crucial for stability.
BASAL METABOLIC RATE (BMR): The number of calories the body burns at rest to maintain basic physiological functions.
BCAAS: (Branched-Chain Amino Acids) Essential amino acids—leucine, isoleucine, and valine—important for muscle protein synthesis.
BODY COMPOSITION: The ratio of lean mass (muscle, bone, water) to fat mass in the body.
CALORIE DEFICIT: A state where calorie expenditure exceeds intake, leading to weight and fat loss.
CALORIE SURPLUS: Consuming more calories than the body uses, necessary for muscle growth.
CARDIORESPIRATORY ENDURANCE: The ability of the heart and lungs to supply oxygen during sustained physical activity.
CARDIOVASCULAR ENDURANCE: The efficiency of the heart, lungs, and blood vessels in delivering oxygen during prolonged exercise.
COMPOUND EXERCISES: Movements that work multiple muscle groups at once, such as squats, deadlifts, and bench presses.
DECONDITIONING: Loss of fitness due to inactivity or insufficient training stimulus.
DOMS: (Delayed Onset Muscle Soreness) Muscle soreness occurring 24–72 hours after exercise due to microscopic muscle damage.
DYNAMIC STRETCHING: Active movements that stretch muscles to their full range of motion, often used as part of a warm-up.
ECCENTRIC CONTRACTION: Muscle lengthening under tension, such as lowering a weight during a bicep curl.
ELECTROLYTES: Minerals like sodium, potassium, and magnesium that regulate muscle contraction and hydration.
ENDURANCE: Endurance is the ability of the body or a specific muscle group to sustain prolonged physical activity without fatigue.
ENDURANCE TRAINING: Exercise designed to improve stamina and aerobic capacity.
FAT OXIDATION: The process of breaking down stored fat for energy.
FFM: (Fat-Free Mass) All body components excluding fat, including muscle, bone, and organs.
FLEXIBILITY: The ability of joints and muscles to move through a full range of motion.
GLYCOGEN: Stored carbohydrates in muscles and the liver used for energy during exercise.
GLYCOLYSIS: The metabolic pathway that breaks down glucose to produce energy.
HIIT: A training method alternating between intense bursts of activity and fixed periods of less-intense activity or rest.
HYPERPLASIA: An increase in the number of muscle fibers (controversial in humans; most growth is via hypertrophy).
HYPERTROPHY: An increase in the size of muscle cells, often the goal of resistance training.
INSULIN SENSITIVITY: How effectively cells respond to insulin and absorb glucose from the bloodstream.
ISOMETRIC EXERCISE: Muscle contraction without joint movement, such as planks or wall sits.
LACTIC ACID: A byproduct of anaerobic metabolism associated with muscle fatigue.
LEAN BODY MASS: Total body weight minus fat mass.
LIGAMENT: Tough, fibrous tissue that connects bone to bone at joints.
MACRONUTRIENTS: Protein, carbohydrates, and fats—the main energy-providing nutrients.
METABOLIC ADAPTATION: The body’s adjustment to prolonged calorie restriction, often reducing calorie expenditure.
METABOLISM: The sum of all chemical processes in the body that convert or use energy.
MOBILITY: The ability to move joints actively through a full range of motion.
MUSCULAR ENDURANCE: The ability of a muscle or group of muscles to sustain repeated contractions over time.
MUSCULAR STRENGTH: The maximal force that a muscle or muscle group can generate in a single effort.
NEUROMUSCULAR ADAPTATION: Improvements in strength due to better nervous system efficiency rather than muscle growth.
OSTEOPOROSIS: A condition characterized by weak and brittle bones, increasing fracture risk.
OVERLOAD PRINCIPLE: Gradually increasing stress placed on the body during exercise to stimulate adaptation and improvement.
OVERTRAINING: A condition caused by excessive training without adequate recovery, leading to fatigue and reduced performance.
PROGRESSIVE OVERLOAD: The systematic increase of stress placed on the body during training to stimulate muscle growth and strength gains.
PROTEIN SYNTHESIS: The process by which the body builds new muscle tissue.
RANGE OF MOTION: The distance a joint can move in different directions.
RANGE OF MOTION (ROM): The full movement potential of a joint, usually its range from flexion to extension.
RECOVERY: The process by which the body repairs and strengthens itself after training.
REPETITION: One complete movement of an exercise, from start to finish.
RESISTANCE TRAINING: Exercise that causes the muscles to contract against an external resistance, such as weights or bands.
RESTING HEART RATE: The number of heartbeats per minute while at rest, often used as a fitness indicator.
SARCOPENIA: Age-related loss of muscle mass and strength.
SKELETAL SYSTEM: The skeletal system is the body’s structural framework, consisting of bones, cartilage, ligaments, and tendons, providing support, protection, enabling movement, and storing minerals and fat.
STABILIZER MUSCLES: Muscles that support joints during movement.
STATIC STRETCHING: Stretching a muscle to its farthest point and holding that position.
STRENGTH TRAINING: Exercise designed to improve muscle strength and power.
TENDON: Fibrous tissue that connects muscle to bone.
THERMOGENESIS: Heat production in the body, contributing to calorie expenditure.
TRAINING VOLUME: Total amount of work performed (sets × reps × load).
VO₂ MAX: The maximum rate of oxygen consumption measured during incremental exercise; a key indicator of aerobic endurance.
WARM-UP: Low-intensity activity performed before exercise to prepare the muscles and cardiovascular system.
WORK CAPACITY: The amount of physical work an individual can perform and recover from.
