Read the notes, then try the practice. It adapts as you go.When you're ready.
Session Length
~17 min
Adaptive Checks
15 questions
Transfer Probes
8
Strength training, also known as resistance training, is a form of physical exercise that uses external resistance or body weight to induce muscular contraction, building the strength, size, anaerobic endurance, and density of skeletal muscles. It operates on the principle of progressive overload, which states that muscles must be challenged with gradually increasing demands in order to adapt and grow stronger over time. The practice encompasses a wide range of modalities including free weights such as barbells and dumbbells, machine-based resistance, bodyweight exercises, resistance bands, and kettlebells, each offering distinct mechanical advantages for different training goals.
The physiological basis of strength training centers on the process of muscle hypertrophy and neuromuscular adaptation. When muscles are subjected to sufficient mechanical tension, metabolic stress, and muscle damage during a training session, the body initiates a repair process that synthesizes new contractile proteins, particularly actin and myosin, resulting in larger and stronger muscle fibers. Equally important are the neural adaptations that occur, especially in beginners, where the nervous system learns to recruit more motor units simultaneously and fire them at higher rates, producing greater force output even before significant muscle growth occurs.
Beyond aesthetics and athletic performance, strength training has been conclusively linked to a broad spectrum of health benefits supported by decades of research. It increases bone mineral density, reducing the risk of osteoporosis; improves insulin sensitivity and glucose metabolism, helping prevent and manage type 2 diabetes; enhances cardiovascular health markers including blood pressure and lipid profiles; supports joint health and reduces chronic pain; and is associated with improved mental health outcomes including reduced symptoms of anxiety and depression. Major health organizations including the World Health Organization and the American College of Sports Medicine recommend that all adults perform resistance training at least two days per week targeting all major muscle groups.
One step at a time.
The gradual increase of stress placed on the musculoskeletal and nervous system during training. This can be achieved by increasing weight, repetitions, sets, training frequency, or decreasing rest periods over time.
Example: A lifter who squats 135 pounds for 3 sets of 8 reps this week aims to squat 140 pounds for 3 sets of 8 reps the following week, systematically increasing the demand on the muscles.
The increase in muscle cell size resulting from resistance training. It occurs primarily through the accumulation of contractile proteins (myofibrillar hypertrophy) and the expansion of fluid and energy stores within the muscle cell (sarcoplasmic hypertrophy).
Example: After several months of consistent bicep curls and progressive overload, a trainee's arm circumference increases from 13 inches to 14.5 inches as the muscle fibers grow in cross-sectional area.
Multi-joint movements that engage multiple muscle groups simultaneously. These exercises allow the lifter to move heavier loads and produce a greater systemic hormonal and metabolic response compared to isolation movements.
Example: The barbell deadlift is a compound exercise that works the glutes, hamstrings, quadriceps, erector spinae, trapezius, forearms, and core musculature all in a single movement pattern.
The maximum amount of weight a person can lift for a single repetition with proper form on a given exercise. It serves as a benchmark for prescribing training intensities, typically expressed as a percentage of 1RM.
Example: A lifter with a bench press 1RM of 225 pounds might train at 75% of 1RM (approximately 170 pounds) for sets of 8-10 reps to target hypertrophy.
The systematic planning of training into distinct phases or cycles that vary in volume, intensity, and exercise selection over time. Periodization prevents plateaus, manages fatigue, and optimizes long-term performance gains.
Example: A powerlifter follows a 12-week linear periodization program: weeks 1-4 focus on high-volume hypertrophy (4 sets of 10 at 65% 1RM), weeks 5-8 on strength (5 sets of 5 at 80% 1RM), and weeks 9-12 on peaking (singles and doubles at 90-100% 1RM).
Improvements in the nervous system's ability to recruit motor units, increase firing rate, and coordinate muscle activation patterns. These adaptations are responsible for most strength gains in the first several weeks of training.
Example: A beginner who increases their squat from 95 to 155 pounds in the first eight weeks of training has gained strength primarily through improved neural drive rather than significant muscle growth.
The total duration a muscle is under mechanical strain during a set. Manipulating tempo (the speed of the eccentric, isometric, and concentric phases) alters time under tension and influences the type of muscular adaptation.
Example: Performing a bicep curl with a 3-second lowering phase, 1-second pause at the bottom, and 2-second lifting phase creates approximately 6 seconds of tension per rep, yielding 60 seconds for a 10-rep set.
The force generated in a muscle when it contracts against an external load. It is considered the primary driver of muscle hypertrophy, stimulating mechanotransduction pathways that signal the muscle to grow.
Example: Holding a heavy barbell during the top portion of a deadlift generates high mechanical tension in the posterior chain muscles, even without movement, triggering an adaptive growth response.
More terms are available in the glossary.
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