Men don’t necessarily need more sleep than women, but several biological factors can make them sleep longer, fall asleep later, and feel sleepier during the day. The reasons range from how their internal clocks are wired to hormonal cycles that depend on deep sleep to medical conditions that disproportionately affect men.
Men’s Internal Clocks Run Slightly Longer
One of the most fundamental reasons men tend to sleep later and longer comes down to their circadian rhythm, the internal clock that governs when the body feels alert and when it feels drowsy. Research published in the Proceedings of the National Academy of Sciences found that men’s internal clocks run on a cycle of about 24 hours and 11 minutes, while women’s average about 24 hours and 5 minutes. That six-minute gap sounds tiny, but it has a real downstream effect: it shifts the timing of melatonin release and body temperature drops by roughly 22 to 28 minutes later in men compared to women.
In practical terms, this means men are biologically nudged toward staying up later and waking up later. Women are significantly more likely to identify as morning types, and about 35% of women have internal clocks that cycle in under 24 hours compared to just 14% of men. So when it looks like a guy is sleeping in while everyone else is up, his body may genuinely be on a later schedule.
Testosterone and the Sleep Connection
Testosterone production is tightly linked to sleep in a way most people don’t realize. Plasma testosterone levels peak during sleep and hit their lowest point in the late afternoon, pulsing roughly every 90 minutes throughout the night. This isn’t just loosely tied to the sleep-wake cycle. The rise in testosterone is sleep-dependent, not driven by the time of day, and it requires at least three hours of uninterrupted deep sleep to happen properly. If sleep is fragmented throughout the night, the testosterone increase doesn’t occur at all.
This creates an interesting feedback loop. The body needs deep sleep to produce testosterone, and testosterone itself influences sleep quality. In a study of men aged 65 and older, those with lower testosterone levels had worse sleep efficiency, more nighttime awakenings, and spent less time in the deep, restorative stages of sleep. When testosterone is low, sleep gets worse, which can make a person feel like they need even more of it.
There’s also a counterintuitive finding: healthy young men with higher natural testosterone levels actually experience greater cognitive decline and more subjective sleepiness after several days of poor sleep compared to men with lower testosterone. In other words, higher testosterone may make men more vulnerable to the effects of not sleeping enough, which could drive them to sleep longer when they get the chance.
Growth Hormone Peaks During Deep Sleep
Testosterone isn’t the only hormone that depends on sleep. About 70% of growth hormone pulses in men occur during deep sleep, and the amount of growth hormone released directly correlates with how much deep sleep a person gets. Growth hormone is essential for muscle repair, tissue recovery, and overall physical maintenance. Men generally carry more muscle mass than women, and that tissue needs regular repair. The body’s primary window for doing this work is during deep sleep stages, which may partly explain why men can feel a strong pull toward longer or deeper sleep, especially after physically demanding days.
Sleep Apnea Hits Men Harder
Obstructive sleep apnea, a condition where the airway repeatedly collapses during sleep, is significantly more common in men than in women. This gender gap begins after puberty (before puberty, rates are similar between boys and girls) and persists throughout adulthood. The condition causes dozens or even hundreds of brief awakenings per night, most of which the sleeper doesn’t remember. The result is sleep that looks adequate by the clock but leaves the person exhausted.
Men and women also experience sleep apnea differently. Men are more likely to report the classic symptoms: loud snoring, gasping, and pauses in breathing. But the daytime consequence is the same: persistent sleepiness, the urge to nap, and difficulty staying alert. Many men who seem to sleep excessively, dozing off on the couch, napping on weekends, sleeping 10 or more hours and still feeling tired, may have undiagnosed sleep apnea that’s destroying the quality of whatever sleep they get.
Low Testosterone and Daytime Sleepiness
Late-onset hypogonadism, the medical term for testosterone levels that decline significantly with age, includes sleep disturbance as one of its hallmark symptoms. The standard screening questionnaire for this condition specifically asks about two sleep-related problems: difficulty falling or staying asleep, and an increased need for sleep combined with persistent tiredness. Research has found that men with sleep disturbances have significantly lower free testosterone levels, and that sleep problems may serve as a clinical marker for more severe testosterone deficiency.
This creates a cycle that can be hard to break. Low testosterone disrupts sleep architecture, leading to poor-quality rest. Poor rest drives daytime sleepiness and fatigue, which looks like excessive sleeping. And because testosterone production depends on deep sleep, the deficit compounds over time. Men experiencing this pattern often don’t connect the dots between their hormone levels and their sleep habits, chalking it up to aging, stress, or laziness.
Depression Can Look Like Oversleeping
Depression in men is notoriously underdiagnosed, and one reason is that it often shows up differently than people expect. While insomnia is the more common sleep symptom of depression overall, hypersomnia (sleeping too much) is a feature of atypical depression and is especially common in younger adults. About 40% of depressed patients under 30 experience excessive sleepiness, compared to roughly 10% of those in their 50s. Among depressed patients broadly, 41% report feeling very sleepy and 40% nap during the day.
Men are also less likely to recognize or report emotional symptoms of depression and more likely to experience it as physical exhaustion, irritability, or withdrawal. Sleeping more than usual, losing interest in activities, and retreating to bed can all be signs of depression masquerading as simple tiredness.
Sleep Restriction Slows the Metabolism
There’s a metabolic dimension worth understanding. When healthy adults are sleep-restricted in controlled studies, their resting metabolic rate, the energy the body burns just to keep itself running, drops by about 2.6%. It returns to normal after recovery sleep. This suggests the body actively conserves energy when sleep-deprived, which may partially explain why someone who has been running on too little sleep for a while can crash hard and sleep for extended periods. The body is essentially recouping an energy debt.
This metabolic slowdown doesn’t differ significantly between men and women in research settings. But because men on average have higher resting metabolic rates due to greater muscle mass, the absolute energy cost of sleep deprivation may be higher, creating a stronger physiological drive to recover that lost sleep.
The Teenage Sleep Surge
If you’re wondering about a teenage boy specifically, the answer is even more straightforward. Adolescents need 9 to 9.5 hours of sleep per night, about an hour more than they needed at age 10. During puberty, the circadian clock shifts later, making teens biologically inclined to fall asleep later and wake up later. For boys, this shift coincides with rapid increases in testosterone production, which as noted above depends heavily on deep sleep. The combination of a later-shifting clock, higher sleep needs, and surging hormones that require sleep to be produced makes teenage boys some of the sleepiest people on the planet. What looks like laziness is often their bodies doing exactly what the developmental stage demands.