title: Effects of endurance training only versus same-session combined endurance and strength training on physical performance and serum hormone concentrations in recreational endurance runners.
abstract: This study investigated the effects of endurance training only (E, n = 14) and same-session combined training, when strength training is repeatedly preceded by endurance loading (endurance and strength training (E+S), n = 13) on endurance (1000-m running time during incremental field test) and strength performance (1-repetition maximum (1RM) in dynamic leg press), basal serum hormone concentrations, and endurance loading-induced force and hormone responses in recreationally endurance-trained men. E was identical in the 2 groups and consisted of steady-state and interval running, 4-6 times per week for 24 weeks. E+S performed additional mixed-maximal and explosive-strength training (2 times per week) immediately following an incremental running session (35-45 min, 65%-85% maximal heart rate). E and E+S decreased running time at week 12 (-8% ± 5%, p = 0.001 and -7% ± 3%, p < 0.001) and 24 (-13% ± 5%, p < 0.001 and -9% ± 5%, p = 0.001). Strength performance decreased in E at week 24 (-5% ± 5%, p = 0.014) but was maintained in E+S (between-groups at week 12 and 24, p = 0.014 and 0.011, respectively). Basal serum testosterone and cortisol concentrations remained unaltered in E and E+S but testosterone/sex hormone binding globulin ratio decreased in E+S at week 12 (-19% ± 26%, p = 0.006). At week 0 and 24, endurance loading-induced acute force (-5% to -9%, p = 0.032 to 0.001) and testosterone and cortisol responses (18%-47%, p = 0.013 to p < 0.001) were similar between E and E+S. This study showed no endurance performance benefits when strength training was performed repeatedly after endurance training compared with endurance training only. This was supported by similar acute responses in force and hormonal measures immediately post-endurance loading after the training with sustained 1RM strength in E+S.
authors.affiliation: a Department of Biology of Physical Activity, PO Box 35 (VIV), 40014, University of Jyväskylä, Finland.
authors.forename: Moritz
authors.initials: M
authors.lastname: Schumann
authors.forename: Olli-Pekka
authors.initials: OP
authors.lastname: Mykkänen
authors.forename: Kenji
authors.initials: K
authors.lastname: Doma
authors.forename: Raffaele
authors.initials: R
authors.lastname: Mazzolari
authors.forename: Kai
authors.initials: K
authors.lastname: Nyman
authors.forename: Keijo
authors.initials: K
authors.lastname: Häkkinen
mesh_terms: D000328:Adult; D000465:Algorithms; D054874:Athletic Performance; D015444:Exercise; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism; D007866:Leg; D008297:Male; D053580:Muscle Strength; D010807:Physical Endurance; D005082:Physical Exertion; D011998:Recreation; D055070:Resistance Training / Q000009:adverse effects; D012420:Running; D012738:Sex Hormone-Binding Globulin / Q000032:analysis* / Q000378:metabolism; D013739:Testosterone / Q000097:blood* / Q000378:metabolism
chemical_list: D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D006854:Hydrocortisone
keywords: acute interference; adaptations hormonales; concurrent training; cortisol; course d’endurance; endocrine adaptations; endurance running; entraînement concurrent; interférence immédiate; loading responses; réponses à la surcharge; testosterone; testostérone