Acute Effects of Resistance Exercise and the Use of GH or IGF-1 Hormones on Oxidative Stress and Antioxidant Markers in Bodybuilders.

Heidar Mohammadjafari,Nematollah Nemati,Tahereh Bagherpoor,Hamid Arazi,Katsuhiko Suzuki

doi:10.3390/antiox8120587

Abstract

The aim of this study was to examine the influence of peptide hormone use on oxidative stress and antioxidant responses to a single session of resistance exercise in male bodybuilders. Forty-five male bodybuilders were divided into three groups: bodybuilders using growth hormone for at least 1 year (i.e., 3 to 4 times in the year) (GH-user, n = 15), bodybuilders using insulin-like growth factor-1 for at least 1 year (i.e., 3 to 4 times in the year) (IGF-1-user, n = 15), and peptide hormone-free bodybuilders (Non-user, n = 15). The heavy resistance exercise protocol consisted of five sets with 80% of one repetition maximum for six exercises. Blood samples were obtained pre and post heavy resistance exercise (HRE) in order to evaluate changes in oxidative stress (8-hydroxy-2-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and nitric oxide (NO)) and antioxidant biomarkers (glutathione peroxidase (GPx), catalase (CAT) and glutamate (GLU)) level. All the experimental groups showed increases in MDA (p = 0.038), NO (p = 0.028), GPx (p = 0.012), and GLU (p = 0.003) concentrations after resistance exercise. For 8-OHdG, the Non-user and IGF-1-user groups indicated increases at post-exercise (p = 0.001), without any significant changes in the GH-user group (p = 0.87). In addition, the changes in serum GPx and GLU levels were greater for the GH-user group than the Non-user and IGF-1-user groups (p = 0.001). In conclusion, HRE induced significant increases in 8-OHdG (except to GH-user group), MDA, NO, GPx, and GLU levels with greater changes in GPx and GLU for the GH-user group.

Highlights

Use of peptide hormones has increased among athletes especially in some bodybuilders to improve lean body mass or fat free mass, muscle size, protein synthesis and decrease body fat [1]
The heavy resistance exercise (HRE) induced a significant change in 8-OHdG biomarker levels for the Non-user and insulin-like growth factor 1 (IGF-1)-user groups (F = 3.08, p = 0.001), without any significant change for the growth hormone (GH)-user group (F = 0.13, p = 0.87)
We found that HRE induced increases in 8-OHdG, MDA, nitric oxide (NO), GPx and GLU levels at post-exercise for all the groups

Summary

Introduction

Use of peptide hormones has increased among athletes especially in some bodybuilders to improve lean body mass or fat free mass, muscle size, protein synthesis and decrease body fat [1]. Amounts of some hormones may be useful in some pathological conditions, injections of peptide hormones (i.e., GH and IGF-1) are widely abused by some athletes and bodybuilders to enhance performance and for this goal World Anti-Doping Agency (WADA) prohibited the use of Antioxidants 2019, 8, 587; doi:10.3390/antiox8120587 www.mdpi.com/journal/antioxidants. Liu et al [4] in a systematic review reported that use of GH could improve body composition and increased lean mass following resistance training intervention. Meinhardt et al [5] examined the effect of a 2 mg dose of GH on body composition and performance adaptations and found that resistance training plus GH injection increased athletic exercise performance and participants that received GH retained more body fluid and had more frequent joint pain than the control group

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