The Paradox of Overtraining: How Stress, Overwork, and Under-Recovery Can Lead to Weight Gain
In the pursuit of fitness and fat loss, many individuals fall into the trap of overtraining, assuming that more exercise and fewer calories are the key to a leaner physique.
However, this approach often backfires, resulting in increased fat accumulation—particularly around the midsection—chronic fatigue, and even illness. Central to this paradox is the body’s stress response, particularly the role of the hormone cortisol, and how excessive training without adequate recovery can compromise hormonal balance, increase inflammation, and disrupt metabolic function.
Cortisol: The Double-Edged Sword
Cortisol, a glucocorticoid hormone released by the adrenal glands, plays a central role in the body’s response to stress. In acute situations, cortisol mobilises energy stores to help the body respond to immediate threats. However, when stress becomes chronic—whether due to emotional pressure, sleep deprivation, or intense exercise—cortisol levels remain elevated, leading to a cascade of negative metabolic effects.
One of cortisol’s key actions is to increase gluconeogenesis (the production of glucose from non-carbohydrate sources) and inhibit insulin, both of which elevate blood sugar levels (Sapolsky, 2004). Chronically high cortisol can result in visceral fat accumulation—fat stored around the internal organs—particularly around the abdomen (Epel et al., 2000).
This type of fat is not only harder to lose but also more metabolically active and associated with a greater risk of metabolic syndrome and cardiovascular disease.
Stress, Inflammation, and Weight Loss Resistance
Chronic psychological and physiological stress not only raises cortisol but also contributes to systemic inflammation. Elevated inflammatory markers such as C-reactive protein (CRP), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-α) have been associated with obesity and difficulty losing weight (Hotamisligil, 2006). These markers interfere with insulin signalling and promote the storage of fat, especially in stressed individuals who are dieting or overexercising.
Moreover, persistent inflammation reduces the efficiency of leptin—the hormone responsible for satiety signalling—making it harder to regulate hunger and fullness (Tilg & Moschen, 2006). As a result, individuals may feel hungrier and more prone to overeating, even when they are consciously trying to restrict calories.
Calorie Restriction and Overtraining: A Dangerous Combination
While caloric deficits are essential for fat loss, they become counterproductive when combined with overtraining and chronic stress. When the body is in a state of energy deficiency and stress simultaneously, it prioritises survival over fitness. This leads to suppressed thyroid function (hypothyroidism), decreased reproductive hormones (such as testosterone and oestrogen), and impaired immune function (Gleeson et al., 2011).
n women, this often presents as amenorrhea (loss of menstrual cycle), and in men, it can lead to reduced libido and muscle mass. Both genders are at risk for overtraining syndrome, characterised by fatigue, depression, sleep disturbances, and increased susceptibility to illness (Kreher & Schwartz, 2012). In such states, calorie restriction only exacerbates hormonal imbalance, leading to chronic fatigue, frequent infections, and ironically, fat gain rather than loss.
Important – Don’t judge a trainer or a training programme on how tired they can make you feel, judge them on the results that they provide!
Training…NOT Draining! 🙏🙏🙏
Until next time stay awesome!
Vanessa x
