Author(s): VAN HAEFTEN, L., BEATTIE, K., HEALY, R., FLANAGAN, E., NÍ CHÉILLEACHAIR, N., Institution: TECHNOLOGICAL UNIVERSITY OF THE SHANNON , Country: IRELAND, Abstract-ID: 663

INTRODUCTION:
Running economy, defined as the oxygen cost of running at a given submaximal speed, is a key determinant of performance in elite middle- long-distance runners. Strength training has demonstrated positive effects on improving running economy in this population. In contrast, evidence regarding the effects of speed-based training on running economy remains equivocal.

METHODS:
A systematic search was conducted across, PubMed, EBSCO, SPORTDiscus, and Medline for articles published up to November 2025. Studies were included if they met the following criteria: (1) population; competitive middle and long-distance runners (≥ 800m), aged ≥18 years, with minimum VO₂max values of ≥ 55 mL·kg-1·min-1 for males, and ≥ 45 mL·kg-1·min-1 for females; (2) intervention; a speed (i.e., acceleration, maximum-velocity, or speed endurance training) or strength training programme (i.e. maximal-, explosive-, reactive-, special- or combined-strength training) performed in addition to or partially replacing endurance training for ≥ 2 weeks, with ≥ 1 weekly sessions; (3) comparator; studies included a control group that performed endurance running training but did not receive any form of strength or speed training; (4) outcomes; running economy was recorded in at least one speed before and after the strength or speed training intervention, running economy expressed as either oxygen cost or energy cost; (5) study design; randomised and non-randomized controlled studies. Random-effects meta-analysis were conducted to examine the effects of maximal strength, reactive strength, combined strength, and speed on running economy.
RESULTS:
The pooled analysis demonstrated that reactive strength, maximum strength and combined strength training, elicited moderate, statistically significant improvements in running economy, whereas speed-based training did not show a consistent or significant effect. Seventeen studies (350 participants; 312 males, 38 females) were included, with participants aged 20.2 – 40.3 years (mean 28.8 years), and VO₂max range was 50.5 – 70.4 mL·kg-1·min-1. Interventions lasted 4 to 12 weeks with one to three weekly sessions. Reactive strength training showed a robust moderate improvement in run economy (SMD = -0.47; 95%, p = 0.003), whereas maximal strength (SMD = -0.69; p = 0.048) and combined strength training (SMD = -0.46; p = 0.029 demonstrated moderate but non-robust effects. Speed training showed a non-significant, and highly heterogeneous effect (SMD = -0.45; 95% CI: -2.32; 1.41, p = 0.633; I² = 93.1%).
CONCLUSION:
Reactive, maximal, and combine strength training elicit moderate improvements in running economy in well-trained middle long-distance runners, whereas speed-based training does not currently demonstrate a consistent effect. These findings highlight the importance of appropriately, dosed individualised strength training in this population and underscore in need for high-quality research to clarify the role of speed training, for improvements in running economy.