title: IGF-1 response to arm exercise with eccentric and concentric muscle contractions in resistance-trained athletes with left ventricular hypertrophy.
abstract: The study aimed at evaluating changes in plasma levels of insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3), testosterone, growth hormone (GH), cortisol, and insulin in resistance-trained male athletes with (n=9) and without (n=9) left ventricular hypertrophy (LVH) in response to eccentric (ECC) and concentric (CON) arm exercise. 10 age-matched healthy non-trained subjects served as controls. M-mode and 2D Doppler echocardiography were used to estimate LV mass.Resting IGF-1 concentration was higher in LVH athletes compared to controls (52 ± 5 nM vs. 46 ± 7 nM, p<0.05). ECC exercise resulted in higher (p<0.05) serum IGF-1 concentrations in athletes with LVH (70 ± 11 nM, n=9) compared to those without LVH (62 ± 10 nM, n=9), and to untrained controls (54 ± 6 nM). Both CON and ECC exercise resulted in higher serum IGFBP-3 levels in LVH athletes compared to controls (242 ± 57 and 274 ± 58, athletes, vs. 215 ± 63 and 244 ± 67, controls, nM, p<0.05). In ECC exercise, GH concentrations were lower in LVH than in non-LVH athletes (4.7 ± 2.1 vs. 6.1 ± 1.8 ng  mL(-1), p<0.05). No differences in other hormones were found between groups. In conclusion, LVH is accompanied by elevated resting serum IGF-1 and enhanced response to eccentric arm exercise. These findings suggest a role of IGF-1, possibly released from contracting muscle, in stimulating LV hypertrophy in resistance training.
authors.affiliation: Department of Physiology and Medicine of Sport, Academy of Physical Education, Katowice, Poland. olazebrowska@yahoo.com
authors.forename: A
authors.initials: A
authors.lastname: Żebrowska
authors.forename: Z
authors.initials: Z
authors.lastname: Waśkiewicz
authors.forename: A
authors.initials: A
authors.lastname: Zając
authors.forename: Z
authors.initials: Z
authors.lastname: Gąsior
authors.forename: H
authors.initials: H
authors.lastname: Galbo
authors.forename: J
authors.initials: J
authors.lastname: Langfort
mesh_terms: D001132:Arm / Q000502:physiology*; D056352:Athletes; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D005080:Exercise Test; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D017379:Hypertrophy, Left Ventricular / Q000097:blood* / Q000000981:diagnostic imaging / Q000209:etiology; D007328:Insulin / Q000097:blood; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D055070:Resistance Training; D013739:Testosterone / Q000097:blood; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D015415:Biomarkers; C515497:IGFBP3 protein, human; D007328:Insulin; D018972:Insulin-Like Growth Factor Binding Protein 3; D019382:Human Growth Hormone; D013739:Testosterone; D007334:Insulin-Like Growth Factor I; D006854:Hydrocortisone