Health science reports2026n = 30
RCTHuman
This study compared how two types of high-intensity exercise affect hunger hormones, appetite, and body composition in overweight and obese men. Thirty men were split into groups doing either running-based…
2026n = 10,027 men in population studies, 51 men in clinical trial
OtherHuman
This study built a better way to read testosterone in men, especially men with obesity, by accounting for SHBG (sex hormone-binding globulin, a protein that binds testosterone and sets how…
Gut microbes2026n = 19
RCTHuman
This study set out to see how swapping some animal protein for plant protein affects gut bacteria and tryptophan processing in men at risk for heart and metabolic problems. It…
Obesity (Silver Spring, Md.)2026n = 17
RCTHuman
This study set out to see if cutting protein while keeping calories the same could help men with overweight or obesity lose weight. Seventeen men were randomly assigned to eat…
Journal of cachexia, sarcopenia and muscle2026n = 68 (37 HIIT + L-citrulline, 31 HIIT + placebo)
RCTHuman
This study looked at how high-intensity interval training (HIIT), where short bursts of hard effort alternate with easier recovery periods, with or without L-citrulline (an amino acid that may boost…
Journal of obesity2026n = 20
RCTHuman
This study tested whether pairing intermittent fasting with weightlifting improves body composition in obese men. It randomly assigned 20 obese men aged 20 to 30 to either a normal diet…
The journal of sexual medicine2026n = 639 men across 10 studies
Systematic ReviewHuman
This systematic review set out to assess how GLP-1 receptor agonists (a class of diabetes and weight-loss drugs) affect male reproductive hormones, semen quality, and metabolic health. It pooled data…
Clinical nutrition research2026n = 4,819
Cross SectionalHuman
This study looked at whether vitamin D levels are linked to metabolic health, measured by the TyG index (a score from fasting blood sugar and triglycerides that flags insulin resistance,…
Human reproduction update2026n = 32 studies included
Meta AnalysisHuman
This study set out to review how different weight loss methods affect male fertility in men with obesity. It looked at 32 studies that compared lifestyle changes, medications, and bariatric…
Scientific reports2026n = 34
RCTHuman
This study compared two exercise approaches, high-intensity functional training (HIFT) and traditional resistance training (RT), for improving metabolic, inflammatory, and physical health in overweight men. Thirty-four men with an average…
American journal of men's health2026n = 7,418
Cross SectionalHuman
This study set out to explore how obesity and chronic inflammation relate to testosterone levels in men. It analyzed data from over 7,400 adult men in the US, using body…
Asian journal of andrology2026n = 3336
Cross SectionalHuman
This study set out to examine how modifiable lifestyle factors like smoking, drinking, and weight affect semen quality in men. It analyzed data from over 3,300 men visiting a fertility…
Frontiers in physiology2026n = 369
Meta AnalysisHuman
This systematic review and meta-analysis looked at how combining aerobic exercise with other interventions affects metabolic, heart, and inflammation markers in men. It pooled data from 14 randomized controlled trials…
Journal of endocrinological investigation2026
Narrative ReviewHuman
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…
Nutrients2026n = 28 participants
OtherHuman
This study set out to compare how men and women respond to a 12-week Mediterranean-style weight-loss diet, focusing on changes in body fat, eating habits, and mental health. It followed…
Aging clinical and experimental research2026n = 30
RCTHuman
This study set out to see if combining creatine (a compound stored in muscle that helps regenerate quick energy) and β-hydroxy-β-methylbutyrate (HMB, a muscle-preserving supplement) with exercise could improve mobility…
Frontiers in public health2026
Meta AnalysisHuman
This study compared two approaches to resistance training, linear periodization (a steady progression of weight up and reps down over months) and undulating periodization (varying weight and reps week to…
Cureus2026n = 100
Cross SectionalHuman
This study looked at how different measures of obesity relate to semen quality in men from infertile couples who had no other known fertility risks. It compared body mass index…
Cureus2026
Narrative ReviewHuman
This is a narrative review (an expert summary of existing research, not a new experiment) asking whether testosterone replacement therapy (TRT) could help men with low testosterone hold onto muscle…
Human reproduction open2025n = 223
Cross SectionalHuman
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…
PeerJ2025n = 22 participants
RCTHuman
This study compared two ways of organising the same lifting session in untrained young men. The test method was cluster set resistance training, meaning a set is broken into small…
Current opinion in urology2025
Narrative ReviewHuman
This review gathers recent evidence on what damages male fertility and how much of it can be undone. Smoking raises sperm DNA fragmentation (breaks in the genetic material inside sperm)…
Reproductive biology and endocrinology : RB&E2025n = 2,430
Cross SectionalHuman
This study looked at whether obesity speeds up the decline in sperm quality that has been seen over time. Researchers reviewed semen tests from 2,430 men with normal sperm counts…
Frontiers in endocrinology2025n = 304
CohortHuman
This study looked at how different types of exercise affect body composition during weight loss. It compared resistance training, aerobic exercise, and no exercise in 304 adults on a calorie-restricted…
Nutrients2025n = 358
Cross SectionalHuman
This study looked at how diet relates to sperm quality, comparing the Mediterranean diet, which is built on seasonal, fresh and whole foods, against ultra-processed foods, which are high in…
Asia Pacific journal of clinical nutrition2025n = 321
RCTHuman
This study tested whether a workplace canteen could improve the health of men with metabolic syndrome (a cluster of a large waist, high blood pressure, high blood sugar, high triglycerides,…
Frontiers in endocrinology2025n = 8,443 men (3,467 normal BMI, 3,444 overweight, 1,532 obese)
Meta AnalysisHuman
This meta-analysis (a study that statistically pools many earlier studies) looked at how body mass index (BMI, a weight-for-height number used to flag over- or under-weight) relates to sperm quality…
Nutrients2025n = 38 (20 placebo, 18 ashwagandha)
RCTHuman
This study set out to see whether ashwagandha, a herb widely sold for stress and performance, adds anything to interval training. Interval training here meant repeated hard efforts on a…
Journal of clinical medicine2024n = 73
Cross SectionalHuman
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…
Andrology2024n = 1,774 participants across 44 studies
Meta AnalysisHuman
This meta-analysis set out to measure how much testosterone men with obesity get back when they lose weight, comparing low-calorie diets with bariatric surgery. It pooled 44 studies covering 1,774…
The American journal of clinical nutrition2020n = 16 (8 per group)
OtherHuman
This study set out to see whether two weeks of eating earlier in the day improves how muscle takes up sugar and amino acids. Sixteen healthy young men were put…
Clinical endocrinology2018
Narrative ReviewHuman
This review looked at the link between obesity and low testosterone in men, focusing on how weight affects hormone levels and what treatments might help. It examined studies on men…
European journal of endocrinology2013n = 24 studies
Meta AnalysisHuman
This study set out to see how losing weight affects testosterone in men with obesity. It pooled 24 trials comparing low-calorie diets against bariatric surgery, measuring changes in total testosterone…
Circulation2011n = 14,345
CohortHuman
This study set out to see how changes in fitness and in body weight affect a man's risk of dying, from any cause and from heart disease. It followed 14,345…