The more sleep you get, the more testosterone your body will produce. Consequently, the less sleep you get, the less testosterone your body will produce. This was confirmed by a 2007 study that measured the testosterone levels of two control groups in the morning, only to find the group that received a full eight hours of sleep had significantly more testosterone when compared to the testosterone levels of the second group, who only were allowed four hours.
This same study concluded that not only does the “testosterone levels of healthy men decline with advancing age”, but also that testosterone levels will fluctuate in accordance with the changes our bodies go through over the course of a natural 24-hour cycle, otherwise known as our circadian rhythm. For males, testosterone production reaches an apex during sleep, and is least active during the afternoon.
While numerous government studies have confirmed that sleep disorders and low testosterone are inextricably related, it has not been until recent years that scientists discovered which caused which. Until fairly recently, most researchers had assumed sleep disorders were responsible for lowering testosterone levels. However, Zoran Sekerovic, a graduate student from the University of Montreal’s Department of Psychology, has proven the opposite: low testosterone is what causes sleep disorders.
By monitoring the brainwaves of males as they slept, and testing their testosterone levels during each phase of sleep, Sekerovic was able to figure out exactly which of the five sleep phases yielded the most testosterone production. He found the most testosterone was produced during phases three and four, which is when a specific kind of brainwave – delta waves – stimulates healing within the body. Sekerovic’s results show that not only does the number of hours of sleep matter, which was already known at the time, but that the quality of sleep matters as well.
The University of Montreal estimates young males spend between 10-20% of their sleep cycle in a“deep sleep”, which includes phases three and four.Since they are able to get enough deep sleep, they are able to produce enough testosterone to avoid further sleeping disorders. By the time a man reaches the age of fifty, however, deep sleep is only maintained for 5-7% of the time, and by the age of sixty, deep sleep may not be possible at all.
This lack of deep sleep means that older males cannot replenish their testosterone levels at a rate fast enough to avoid sleep disorders.Therefore, sleep disorders are a direct result of a lack of testosterone, and not the other way around.