Recovery responses of testosterone, growth hormone, and IGF-1 after resistance exercise

Abstract

The complexity and redundancy of the endocrine pathways during recovery related to anabolic function in the body belie an oversimplistic approach to its study. The purpose of this review is to examine the role of resistance exercise (RE) on the recovery responses of three major anabolic hormones, testosterone, growth hormone(s), and insulin-like growth factor 1. Each hormone has a complexity related to differential pathways of action as well as interactions with binding proteins and receptor interactions. Testosterone is the primary anabolic hormone, and its concentration changes during the recovery period depending on the upregulation or downregulation of the androgen receptor. Multiple tissues beyond skeletal muscle are targeted under hormonal control and play critical roles in metabolism and physiological function. Growth hormone (GH) demonstrates differential increases in recovery with RE based on the type of GH being assayed and workout being used. IGF-1 shows variable increases in recovery with RE and is intimately linked to a host of binding proteins that are essential to its integrative actions and mediating targeting effects. The RE stress is related to recruitment of muscle tissue with the glandular release of hormones as signals to target tissues to support homeostatic mechanisms for metabolism and tissue repair during the recovery process. Anabolic hormones play a crucial role in the body's response to metabolism, repair, and adaptive capabilities especially in response to anabolic-type RE. Changes of these hormones following RE during recovery in the circulatory biocompartment of blood are reflective of the many mechanisms of action that are in play in the repair and recovery process.

Growth Hormone(s), Testosterone, Insulin-Like Growth Factors, and Cortisol: Roles and Integration for Cellular Development and Growth With Exercise

“…Thus, it is currently unclear if DHT is more anabolic in skeletal muscle than T alone. Testosterone performs a multitude of ergogenic, anabolic, and anti-catabolic functions in skeletal muscle and neuronal tissue leading to increased muscle strength, power, endurance, and hypertrophy in a dose-dependent manner (1). Genomic androgen/AR binding may alter the expression of more than 90 genes, several of which are involved in the regulation of skeletal muscle structure, fiber types, metabolism, and transcription (6).…”

“…In women, studies show no or limited acute elevations. The magnitude of the acute responses is affected by many factors including the demands of the protocol, nutritional intake, training experience but mostly due to plasma volume reductions and reduced clearance (1). The ramifications of acute elevations during RT are unclear but appear to be part of the macro-signaling cascade affecting, in part, muscular adaptations.…”

“…work in a similar manner. All stages from production, release, transportation, tissue uptake, and intracellular signaling must be considered in an integrative manner to accurately portray the effects of the hormone-receptor interaction (1). Thus, viewing only a fraction of the signaling chain may underrepresent the entirety of the hormonal actions.…”

A randomised-controlled trial pilot study examining the effect of pelvic floor muscle training on steroid hormone concentrations in elderly women with stress urinary incontinence

“…It should be noted that greater changes in testosterone concentration during physical activity are observed in people engaged in little physical activity than in professional athletes [17]. Numerous studies demonstrate that physical activity of varying intensity levels affects testosterone concentrations in young women [18][19][20][21][22]. Fewer data are available on hormonal changes in elderly women, induced by physical activity, and there are discrepancies among these results [23][24][25][26].…”

Replace, restore, revive: the keys to recovery after exercise

“…It outlines the time course of changes in the transcriptional responses in skeletal muscle and the relationship between gene expression, muscle protein synthesis, and phenotypic adaptations to exercise. The next article by Kraemer, Ratamess, and Nindl is titled "Recovery from exercise: recovery responses of testosterone, growth hormone, and IGF-1 after resistance exercise" (8). It provides a paradigm that links testosterone, growth hormone, and IGF-1 to recovery and also to adaptation to exercise training.…”