Reframing the problem from 'overtraining' to 'under-recovering' removes the negative connotation of exercising too much. Instead, it positively frames the solution as needing more fuel and better rest, making it a more acceptable and actionable approach for motivated individuals.
Staying in the moderate intensity zone (e.g., Zone 3-4) elevates cortisol and inflammation without providing a strong enough adaptive signal. For perimenopausal women, this is particularly detrimental. The solution is polarizing training: mixing very high intensity with very low intensity recovery work.
Many women misunderstand 'heavy lifting,' opting for light weights and high reps for 'toning.' True heavy lifting involves a weight that is ~80% of your one-rep max, leading to failure after just a few repetitions. This is what stimulates significant strength and muscle adaptation.
From an evolutionary perspective, a woman's body interprets a calorie deficit as famine, triggering fat storage and halting reproduction to survive. A man's body interprets the same deficit as a signal to hunt, leaning out and increasing cognitive focus to find food. This is a key sex-based metabolic difference.
Contrary to appearances, very lean female long-distance runners can have high levels of visceral fat around their organs. This is caused by chronic inflammation, low energy intake, and suppressed estradiol from their training regimen, creating a hidden health risk despite a low body weight.
High-intensity exercise produces lactate, which serves as a preferential fuel for the heart and brain. This can help offset age-related declines in the brain's glucose metabolism—a factor in Alzheimer's, which disproportionately affects women—making HIIT a tool for long-term cognitive preservation.
Our bodies evolved to handle episodic stress (e.g., a lion) by releasing glucose for immediate physical action. Modern chronic stress (e.g., a bad meeting) triggers the same hormonal response, but the glucose goes unused as we remain sedentary, contributing to metabolic issues and inflammation.