Research on sleep loss and disruption in men, and what it costs hormones, recovery, and metabolism.
This study tested whether a six-week, unsupervised high-intensity interval training (HIIT) running program on campus could improve fitness, sleep, and body composition in sedentary male university students. Fifty-six students were…
This study set out to explore whether lower muscle mass is linked to restless legs syndrome (RLS), a condition that disrupts sleep. Researchers analyzed data from 5,752 adults who underwent…
This study set out to see if moderate-intensity walking could improve glucose tolerance after a night of partial sleep restriction, as high-intensity exercise has been shown to do. Eleven healthy,…
This study set out to explore how coffee, exercise, and sleep relate to semen quality in men. It surveyed 3,302 men aged 18-60, collecting semen samples and lifestyle data through…
This review looked at how aging affects men's hormones, sleep, and metabolism, centering on two kinds of hypogonadism (when the testicles do not make enough testosterone, causing symptoms like low…
This study looked at how depression, testosterone levels, and shift work are linked in men with symptoms of low testosterone. It reviewed medical records and survey data from 766 men…
This study tested how different doses and timing of caffeine affect sleep in men who usually drink moderate amounts. It compared a placebo, 100 mg, and 400 mg of caffeine…
This study looked at whether a heart-healthy lifestyle is linked to better sperm quality in young men, using the American Heart Association's Life's Essential 8 score. That score rates eight…
This study set out to examine how sleep quality and daytime sleepiness together affect injury risk in physically active university students. It analyzed data from 418 students (199 males, 219…
This scoping review set out to map the evidence on how psychosocial work factors affect male fertility and sperm quality. It analyzed 18 peer-reviewed studies from 1990 to 2024, focusing…
This study looked at whether a short, high-dose creatine (a compound stored in muscle that helps regenerate quick energy for short, hard efforts) routine improves sleep, performance, thinking, and recovery…
This study set out to see whether men who like and seek out sunlight have less depression and better sleep. It used 7,306 American men from NHANES (a large, recurring…
This study set out to see how lifestyle and insulin resistance relate to male fertility. Insulin resistance means the body has stopped responding properly to insulin, so it takes more…
This study looked at how light exposure affects sleep in professional athletes. It tracked 17 male Australian Football players for 14 days, using wrist devices to measure sleep and light…
This study set out to measure how the amount of caffeine in the blood tracks with sleep depth and heart activity. Twenty-one healthy young men took either 160 mg of…
This study looked at whether sleep duration affects markers of male fertility in young men. It analyzed 1,055 Danish men who reported their sleep habits and gave semen and blood…
This study looked at whether taking ZMA, a supplement combining zinc, magnesium and vitamin B6, before bed for two nights could improve sleep and next-day performance in healthy active men.…
This study looked at whether short-term sleep loss affects bone health markers in healthy men. Twelve men who normally slept 7-9 hours a night spent time in a sleep lab,…
This meta-analysis set out to clarify how sleep deprivation affects testosterone levels in healthy men. It pooled data from 18 studies involving 252 men, comparing testosterone levels after partial sleep…
This study set out to see how severe sleep restriction affects appetite, food intake, and appetite-regulating hormones in healthy young men. It compared three nights of very little sleep (2…
This study asked whether a man's tendency to zone out after short sleep predicts whether his working memory and spatial skill keep improving with practice. Fifteen healthy young men slept…
This study looked at whether changes in how alert, motivated or effortful a man feels explain why some handle sleep loss better than others. Fifteen healthy young men had three…
This study set out to see whether a regular daytime coffee habit disturbs sleep in young men who already drink it. Twenty men went through three 10 day conditions, daily…
This study set out to compare how young and older men's hormone levels respond to a night without sleep. It measured testosterone, luteinizing hormone (LH, a pituitary hormone that signals…
This study looked at how going without sleep affects muscle recovery after hard exercise. Ten men did 240 hard lengthening contractions of the thigh muscles, then either stayed awake for…
This study looked at whether cutting sleep short changes testosterone in healthy young men, across two separate trials. In the first, 14 men had 4 hours in bed for 5…
This study looked at how sleep duration relates to semen quality and reproductive hormones in young men. It recruited 796 male college students in Chongqing, China and followed up 656…
This study looked at whether catching up on sleep at the weekend improves insulin sensitivity and hormones in men who habitually sleep too little in the week. Nineteen such men…
This study looked at whether poor sleep affects semen quality in young men. It surveyed 953 healthy Danish men aged around military-service age, asking about their sleep patterns and measuring…
This study set out to see how cutting sleep affects glucose handling and hormones in young men. Fourteen healthy men were kept in a laboratory for two nights of 10…