title: Effects of a concurrent strength and endurance training on running performance and running economy in recreational marathon runners.
abstract: The purpose of this study was to investigate the effects of a concurrent strength and endurance training program on running performance and running economy of middle-aged runners during their marathon preparation. Twenty-two (8 women and 14 men) recreational runners (mean ± SD: age 40.0 ± 11.7 years; body mass index 22.6 ± 2.1 kg·m⁻²) were separated into 2 groups (n = 11; combined endurance running and strength training program [ES]: 9 men, 2 women and endurance running [E]: 7 men, and 4 women). Both completed an 8-week intervention period that consisted of either endurance training (E: 276 ± 108 minute running per week) or a combined endurance and strength training program (ES: 240 ± 121-minute running plus 2 strength training sessions per week [120 minutes]). Strength training was focused on trunk (strength endurance program) and leg muscles (high-intensity program). Before and after the intervention, subjects completed an incremental treadmill run and maximal isometric strength tests. The initial values for VO2peak (ES: 52.0 ± 6.1 vs. E: 51.1 ± 7.5 ml·kg⁻¹·min⁻¹) and anaerobic threshold (ES: 3.5 ± 0.4 vs. E: 3.4 ± 0.5 m·s⁻¹) were identical in both groups. A significant time × intervention effect was found for maximal isometric force of knee extension (ES: from 4.6 ± 1.4 to 6.2 ± 1.0 N·kg⁻¹, p < 0.01), whereas no changes in body mass occurred. No significant differences between the groups and no significant interaction (time × intervention) were found for VO2 (absolute and relative to VO2peak) at defined marathon running velocities (2.4 and 2.8 m·s⁻¹) and submaximal blood lactate thresholds (2.0, 3.0, and 4.0 mmol·L⁻¹). Stride length and stride frequency also remained unchanged. The results suggest no benefits of an 8-week concurrent strength training for running economy and coordination of recreational marathon runners despite a clear improvement in leg strength, maybe because of an insufficient sample size or a short intervention period.
authors.affiliation: Department of Coaching Science, Faculty of Sports Science, Ruhr-University, Bochum, Germany. alexander.ferrauti@rub.de
authors.forename: Alexander
authors.initials: A
authors.lastname: Ferrauti
authors.forename: Matthias
authors.initials: M
authors.lastname: Bergermann
authors.forename: Jaime
authors.initials: J
authors.lastname: Fernandez-Fernandez
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology; D056352:Athletes; D054874:Athletic Performance / Q000502:physiology*; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007717:Knee / Q000502:physiology; D019344:Lactic Acid / Q000097:blood; D007866:Leg / Q000502:physiology; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology*; D011998:Recreation / Q000502:physiology*; D055070:Resistance Training; D012420:Running / Q000502:physiology*; D034941:Upper Extremity / Q000502:physiology
chemical_list: D019344:Lactic Acid