Table 2.
Hormones associated with the development and maintenance of lean body tissue and the impact of adiposity and exercise on the production and release by endocrine glands
| Hormone | Endocrine Gland | Tissue Influenced by Hormone (Metabolic response to signal) | Impact of Over-fatness | Impact of Physical Activity (Acute) | Impact of Physical Activity (Chronic) |
|---|---|---|---|---|---|
| Testosterone/Adrenal Androgens [72-82] |
Testes Adrenal Cortex |
Skeletal Muscle (hypertrophy, add contractile tissue) |
↓ with associated ↑ in SHBG |
↑ followed by ↓ |
↔, ↑,↓ |
| Bone (add bone mass) | |||||
| Adipose Tissue (break-down lipid) | |||||
| Growth Hormone [83-86] |
Anterior Pituitary Gland |
Liver (generate IGF, gluconeogenesis, glycogenolysis) |
↓ with associated ↑ in GHBP |
↑ followed by ↓ |
↔, ↑,↓ |
| Skeletal Muscle (hypertrophy, add non-contractile tissue) | |||||
| Bone (add bone mass) | |||||
| Adipose Tissue (break-down lipid for use as fuel source) | |||||
| Insulin [32,44,54,87-96] |
Pancreas |
Skeletal Muscle (glucose, amino acid, lipid uptake and storage) |
↑ (see Figure 8 for rational) |
↑ during exercise bout, ↓following |
↓ |
| Liver (glucose uptake and storage) | |||||
| Adipose Tissue (glucose and lipid uptake and storage) | |||||
| Insulin-like Growth Factor (IGF) [86,97-103] |
Liver, Skeletal Muscle, Bone |
Skeletal Muscle (hypertrophy, add non-contractile and contractile protein) |
↓ with associated ↑ in IGF-BP |
↑followed by ↓ |
↔, ↑,↓ |
| Bone (add bone mass) | |||||
| Cortisol [60,84] |
Adrenal Cortex |
Skeletal Muscle (break-down of protein tissue, lipid break-down, decreased use of glucose) |
↑(see Figure 8 for rational) |
↑ during exercise bout, ↓following |
↔,↓ |
| Bone (break-down of protein matrix) | |||||
| Liver (glycogenolysis) | |||||
| Adipose Tissue (break-down lipid for use as fuel source) | |||||
| Immune Cells (regulation of inflammatory response) | |||||
| Triiodothyronine (T3) [104,105] |
Thyroid |
Skeletal Muscle (regulation of metabolism and fuel source utilization) |
↓ (Hypothyroidism associated with obesity unknown causal relationship) |
↑ during exercise bout, ↓following 60 minutes of recovery |
↔,↑ |
| Bone (regulation of generation of protein matrix) | |||||
| Adipose Tissue (regulation of lipid deposition and utilization) | |||||
| Thyroxin (T4) [104,105] | Thyroid | Skeletal Muscle (regulation of metabolism and fuel source utilization) |
↓ (Hypothyroidism associated with obesity unknown causal relationship) | ↑ following exercise bout, ↓following 120 minutes of recovery | ↔,↑ |
| Bone (regulation of generation of protein matrix) | |||||
| Adipose Tissue (regulation of lipid deposition and utilization) |
Note that ↑ indicates an increase in production and release, ↓indicates a decrease in production and release, ↔ indicates no effect in production and release, and ? Indicates unknown response.