CONTEXT: Historically, physical fitness and exercise training interventions have often been described in relation to training volume metrics (e.g., total sets, repetitions, and session duration). Training frequency and overall training load, which integrates volume, frequency, and intensity, are related but conceptually distinct constructs that are commonly reported alongside volume measures. Although easily quantifiable, these metrics do not reflect outcome performance, such as function, health, wellbeing, quality of life, or the burden of obtaining these outcomes. Emerging evidence suggests that these benefits may be achieved with much smaller doses of training, although a unified framework for performance efficiency is lacking. OBJECTIVE: To systematically review existing literature on exercise dosing, volume, and time efficiency in relation to function, performance, and patient-reported outcomes (PROs), and propose a conceptual framework for the new term "value-based performance" (VBP). DATA SOURCES: The literature databases PubMed (MEDLINE), Web of Science, and Scopus were searched using Boolean operators and combined free-text keywords for the relevant studies reported in accordance with the PRISMA 2020 guidelines. STUDY SELECTION: Studies were selected if they explicitly evaluated the relationship among exercise dose, volume, time and performance, function, and PROs. After stepwise screening and full-text review, 9 studies that met eligibility criteria were qualitatively synthesized, and data on the outcomes gained and the costs of training were extracted and used to build the conceptual framework. STUDY DESIGN: Systematic review with qualitative thematic analysis. LEVEL OF EVIDENCE: Level 3. DATA EXTRACTION: Data extraction focused on parameters related to exercise dose, volume, time, performance, function, and use of PROs. RESULTS: Across resistance, aerobic and high-intensity interval training, time-efficient reduced-dose showed small-to-moderate benefits to performance, functional capacity, and PROs. There was strong evidence for maintenance of benefits, favorable outcome-to-burden ratios, minimum effective dose thresholds and clinically meaningful changes, and less time to benefit. CONCLUSION: This review challenges the conventional, volume-focused definition of performance and that efficiency should also be considered when evaluating exercise. We propose a new approach to defining performance, termed VBP, which describes performance as the ratio of gain in your outcome(s) relative to the cost of obtaining those gains.
Khachfe et al. (Sun,) studied this question.