The Department of Medicine, University of Chicago report the ‘vicious circle’ between weight and sleep problems, noting hormonal dysfunction as a consequence of lack of sleep. Scientists highlight our hunger hormone - grehlin - increases by 28%, our satiety hormone - leptin - decreases 18% with insufficient sleep, and further, we have a 33-45% increase in demand for sugary carbohydrates, due to increased insulin resistance and increased stress. Both factors lead to increased intake of calories, heightening weight problems.
As a result, sleep apnea is more likely: Nature and Science of Sleep highlights 70% of individuals with sleep apnea are obese, with a 10% weight gain predicting a 32% increase in apnea severity. Conversely, a 10% weight loss contributed to a 26% decrease in apnea severity. Insomnia risk is also heightened due to excess weight.
On the other hand, individuals undertaking frequent HIIT or weight training, without an adequate warm down routine, are also at risk - unless you stretch post session, you leave your body in a state of stress: impeding your ability to switch off that evening.