Progressive Resistance Exercise for Quadriceps Strength in Male and Female Athletes: A Critical Narrative Review of Loading Models, Modalities, and Sex-Specific Responses

Abstract

Quadriceps strength is a central determinant of force production, deceleration, jumping, sprinting, change of direction, and knee-joint control in many sports. Progressive resistance exercise is therefore widely prescribed to athletes, yet the phrase encompasses markedly different loading models, contraction modes, equipment, progression rules, and monitoring systems. This critical narrative review evaluates the efficacy of conventional high-load isotonic training, periodised and autoregulated progression, isokinetic loading, eccentric and flywheel methods, variable and elastic resistance, and low-load blood-flow-restriction exercise for improving quadriceps or closely related lower-body strength in male and female athletes. A transparent search of accessible scholarly indexes and citation networks was undertaken for literature published from 1945 to 25 May 2026, with foundational earlier work considered where necessary. Evidence was appraised for design quality, training specificity, participant training status, sex representation, measurement validity, and transfer to athletic performance. The most defensible conclusion is that progressive overload, adequate exposure to high force, and alignment between the trained movement and the strength test are more important than the brand name of a technique. Heavy dynamic training generally provides the clearest advantage for one-repetition-maximum strength, while volume, frequency, and proximity to failure mainly influence whether sufficient high-quality work can be accumulated and recovered from. Isokinetic, eccentric, flywheel, variable-resistance, autoregulatory, and blood-flow-restriction methods can all increase strength, but superiority over well-designed conventional training is inconsistent and usually outcome-specific. Relative lower-body strength gains appear broadly similar in women and men when programmes and baseline training status are comparable, although female athletes remain underrepresented and sex-specific inferences are constrained by small samples and weak control of reproductive-status variables. Advanced methods are best viewed as tools for solving specific programming problems rather than universal replacements for conventional progressive loading. Future trials require adequately powered sex-stratified designs, athlete-specific samples, standardised quadriceps outcomes, transparent progression algorithms, and longer follow-up to establish durability and sport transfer.