Study archive · page 7

In an 8-week randomised trial, resistance-trained men taking 30 g/day whey protein plus 10 g/day collagen gained more muscle mass, lumbar spine bone density and strength than whey alone, collagen alone or placebo.

⚠What it shows: Small double-blind RCT: 40 resistance-trained men across four groups, so about 10 per arm, over only 8 weeks; muscle mass came from bioelectrical impedance rather than a criterion method, and the reported gains — including the spine bone density change — are unusually large and unusually consistent for such a short trial, so independent replication matters.Study · BMC Sports Sci Med Rehabil

Pooling 20 randomised trials in 2,445 adults with metabolic syndrome or related conditions, supplements from the mint and sage family produced modest reductions in BMI, weight, waist circumference and waist-to-hip ratio. Directly measured body fat mass did not change significantly.

⚠What it shows: Meta-analysis of 20 RCTs (n=2,445) in adults with metabolic syndrome, obesity, type 2 diabetes, dyslipidaemia or fatty liver; half the trials had unclear allocation concealment, 10% had high performance bias risk, trials were short, body fat was measured indirectly, and the genus-level signals for Salvia and Zataria came from few trials.Review · J Ethnopharmacol

A meta-analysis of 20 randomised trials in women found acute caffeine gave a small average performance boost (Hedges' g = 0.37), with positive estimates in every menstrual-cycle phase and in contraceptive users, and no clear evidence that phase changes the effect. Certainty was low to very low.

⚠What it shows: Systematic review and meta-analysis of 20 randomised trials with 144 effect sizes in women; risk-of-bias concerns, sparse subgroup data, inconsistent verification of menstrual phase and low-to-very-low GRADE certainty mean subgroup conclusions are hypothesis-generating only.Systematic review · Front Nutr

Across 13 randomised placebo-controlled trials in rugby players, acute caffeine produced small improvements in sprint performance and lower perceived exertion, plus a large but highly heterogeneous effect on passing accuracy. Jumping, strength, metabolic and hormonal markers showed no significant change.

⚠What it shows: Systematic review and meta-analysis of 15 studies (13 in the pooled analysis) in rugby players, but GRADE certainty was low to very low, and the passing-accuracy result showed high heterogeneity and possible small-study effects.Systematic review · Front Nutr

In the 573-person clinic subcohort of the COSMOS trial, a daily multivitamin-mineral supplement produced a more favourable two-year change in episodic memory than placebo (0.12 SD units) but no clear benefit for executive function or attention. Pooling three COSMOS cognitive substudies, the multivitamin improved global cognition by 0.07 SD units, an effect the authors equate to reducing cognitive ageing by 2 years.

⚠What it shows: Meta-analysis of three cognitive substudies (n=573, 2158 and 2472) nested within the single COSMOS trial of adults aged 60 and over, so it is not independent replication; effects were small in size, tests differed between substudies, and no effect was seen on executive function or attention in the clinic subcohort.Meta-analysis · Am J Clin Nutr

In a 12-week randomised trial of virtual reality exercise, participants viewing professionally produced 360° waterscapes improved mental quality of life, fat-free mass and BMI, and reported more restorativeness and less VR sickness than those viewing self-recorded landscapes.

⚠What it shows: Single RCT with 40 vs 32 participants over 12 weeks; the groups differed in video production quality as well as scenery type, and outcomes relied partly on self-report questionnaires.Study · J Formos Med Assoc

In a secondary analysis of 1,726 adults treated for alcohol use disorder, those engaging in more alcohol-free activities 6 months after treatment drank heavily less often at 12 months, and the link was stronger among people living in more impoverished communities. It is an observational association within a trial, not proof that adding activities causes less drinking.

⚠What it shows: Secondary observational analysis of 1,726 participants from a randomised alcohol use disorder trial at 10 US research units; associations come from Bayesian multilevel models over 12 months and cannot establish cause, and the sample is people who completed formal alcohol treatment.RCT · J Exp Anal Behav

An 8-week mindfulness-based stress reduction (MBSR) programme improved quality of life, life satisfaction, mental well-being and sleep quality in a randomised controlled trial of 84 menopausal women, while a no-intervention control group showed no significant change.

⚠What it shows: One single-site RCT in Türkiye, n=84, compared against a no-intervention control rather than a placebo or attention control; outcomes were self-reported and effect sizes were not stated in the abstract.RCT · J Nurs Scholarsh

In a three-arm trial of 122 adults with probable depression, an 8-week multicomponent lifestyle programme delivered either by smartphone app or by booklet cut depressive symptoms more than a waitlist, with clinically significant improvement in 78% of the app group and 55% of the booklet group versus 19.5% of controls.

⚠What it shows: Single randomised trial of 122 adults with probable depression in Hong Kong, compared against a waitlist rather than an active treatment, with follow-up beyond week 9 collected only in the intervention groups.Study · J Affect Disord

Community-dwelling adults aged 55 and over who played a home-based digital mahjong game twice weekly for six months improved slightly more on delayed recall than a no-intervention control group, with a between-group difference of 0.79 points on the Montreal Cognitive Assessment. Diastolic blood pressure also fell 3.50 mm Hg more in the game group, and brain imaging showed increased regional activity coherence in the right insula.

⚠What it shows: Single-blind randomised trial of 60 community-dwelling adults in Taipei, 30 per group, analysed per protocol, with no active control — the comparison group did nothing at all, so attention, novelty and the bundled walking incentive cannot be separated from the game itself. Cognitive gain was under one point on a screening test.RCT · JMIR Aging

A meta-analysis of 63 studies found plyometric training significantly improved jumping (SMD 0.648), sprinting (SMD -0.496) and agility (SMD -0.659) in adolescents aged 10-19, with benefits more consistent when programmes ran at least 10 weeks.

⚠What it shows: Meta-analysis of 63 trials in healthy adolescents aged 10-19; between-study heterogeneity, variable testing protocols, and small sex- and sport-specific subgroups limit generalisability.Meta-analysis · PeerJ

Pooling 29 randomised trials in 1,383 people aged 6-45 with overweight or obesity, combining resistance with aerobic training beat aerobic exercise alone for lean body mass and insulin-resistance markers. Body weight, BMI, body fat percentage, waist circumference, blood pressure and lipids showed no consistent difference.

⚠What it shows: Meta-analysis of 29 randomised trials (n=1,383) in people aged 6-45 with overweight or obesity; several outcomes rested on few studies with low-to-very-low certainty evidence, secondary analyses are exploratory, and the age range spans children to middle-aged adults.Study · iScience

Pooling eight randomised trials, movement retraining substantially reduced peak vertical ground reaction force during landing, a modifiable biomechanical risk marker for ACL injury. No included trial measured actual injury rates, so whether softer landings mean fewer torn ligaments remains unknown.

⚠What it shows: Meta-analysis of nine comparisons from eight randomised trials with only 292 participants in total; certainty of evidence was rated low with substantial heterogeneity (I2 = 63%), the subgroup difference rests on just three general-athletic comparisons, and the outcome is a surrogate marker rather than injury incidence.Review · J Funct Morphol Kinesiol

In 30 office workers with chronic neck pain, eight weeks of supervised Pilates improved pain, disability, cervical range of motion, neck muscle strength and core endurance. Adding kinesiotaping to the same programme gave no extra benefit for pain or disability, and only improved left cervical rotation.

⚠What it shows: Small randomised controlled trial with only 30 office workers completing (16 Pilates, 14 Pilates plus taping), no no-exercise control group, short 8-week follow-up and no blinding of the taping; the authors themselves call for larger studies.RCT · Pain Res Manag

Among 354,957 UK Biobank adults followed for a median of 13 years, those drinking 5 or more cups of coffee a day had lower rates of cirrhosis (hazard ratio 0.68), hepatocellular carcinoma (0.53) and liver-related mortality (0.58), with similar patterns for caffeinated and decaffeinated coffee. Imaging showed lower liver fat, iron and fibroinflammation with higher intake.

⚠What it shows: Large observational cohort, not a trial: coffee intake was self-reported by questionnaire in UK Biobank volunteers who are healthier than the general population. Models adjusted for demographic, behavioural, metabolic and genetic factors, but residual confounding and reverse causation cannot be excluded, so causation is unproven.Study · Clin Gastroenterol Hepatol

A meta-analysis of whole-food dietary interventions in adults aged 50 and over found they raised daily protein intake by 12.2 g/day compared with controls, with bigger effects when programmes ran longer, used individual counselling and set an absolute protein target.

⚠What it shows: Systematic review of 16 studies (n = 1712, 33% male) with a meta-analysis of 11 controlled trials (n = 1207) in community-dwelling older adults; protein intake was self-reported dietary data, the confidence interval was wide (+5.0 to +19.4 g/day), and muscle or strength outcomes were not the endpoint.Study · Nutr Rev

In 50 obese women, 12 weeks of inulin-enriched tapioca pearls produced significant reductions in body weight, BMI, body fat mass, visceral fat, total cholesterol and LDL cholesterol compared with placebo pearls. The abstract reports the direction of change but not the size of it.

⚠What it shows: One randomised, double-blind, placebo-controlled trial in 50 women aged 20-50 with BMI at or above 27 or waist over 80 cm, run for 12 weeks; small, single-site, women only, and the abstract gives no effect sizes, so the reductions could be modest. One author is affiliated with the company behind the product. Needs larger and independent replication.RCT · J Food Drug Anal

Pooling seven randomised trials in adults aged 60 and over, adding protein or amino acids at breakfast did not improve lean mass, grip strength or lower-limb strength. The evidence was judged very uncertain, and in trials without exercise the extra morning protein was linked to slightly lower total daily energy intake.

⚠What it shows: Systematic review and meta-analysis of only 7 RCTs totalling 305 older adults; the authors rate certainty as very low, effect estimates all crossed zero, and they call for further high-quality trials.Review · Food Sci Nutr

Six weeks of home-based Thai-boxing HIIT improved VO2 max, resting blood pressure, resting heart rate, grip strength, trunk endurance and body fat more than a general health-education programme in 58 sedentary young adults. Muscle mass and fat-free mass did not differ between groups.

⚠What it shows: One 6-week RCT, n=58 sedentary young adults in Thailand; short duration, no long-term follow-up, and the comparison group received a different active programme.Study · J Educ Health Promot

Telling people living with HIV their personal 5- and 10-year cardiovascular risk, plus a brief personalised behaviour intervention, significantly improved heart-disease knowledge and reduced some risk behaviours over 6 months. Smoking and drinking rates fell more than in controls but not significantly.

⚠What it shows: Non-randomised multicentre trial (362 matched pairs after propensity-score matching) in people living with HIV in one Chinese province; behaviour changes were modest and several outcomes were not statistically significant.Study · Infect Dis Ther

Among 442 users of a smart ring, the device's "cardio age" estimate correlated with sleep efficiency, REM sleep, sleep duration and daily steps — measures not fed into the algorithm — and 82.6% of users were rated younger than their actual age. All the authors work for the company selling the feature.

⚠What it shows: Retrospective observational analysis of 442 self-selected ring owners over 12 months, run entirely by employees of the company that sells the feature; correlations were weak (around r = -0.2) and no laboratory fitness comparison was reported.Study · Front Digit Health

Machine-learning models classified whether serum miR-210 was raised after exercise training with 90% accuracy — but the entire study was 10 young adults, five per outcome group. Correlations between miR-210 and training frequency or age were weak and non-significant.

⚠What it shows: Exploratory study in just 10 young adults with five people per group, using leave-one-out cross-validation on a tiny sample — accuracy figures from samples this small are highly unstable, and the authors call the work hypothesis-generating.Study · Comb Chem High Throughput Screen

In a Finnish twin cohort followed for a mean 17.5 years, a genetic score for longer lifespan was associated with modestly lower all-cause mortality, largely independent of lifestyle. Smoking 20 or more cigarettes a day and female sex were both stronger predictors than the genetic score.

⚠What it shows: Observational prospective cohort of 5,575 older Finnish twins (mean age 57.4) with 1,405 deaths; associations only, self-reported lifestyle factors, and findings in one national population may not generalise.Study · Geroscience

In a microbiome analysis of adults with mild-to-moderate Crohn's disease on the Crohn's disease exclusion diet, those who sustained remission at both weeks 12 and 24 had a distinct gut profile at baseline — lower alpha diversity and more Alistipes and Faecalibacterium — while Haemophilus and Prevotella were negatively linked to remission.

⚠What it shows: Secondary microbiome analysis of two randomised trials, one in adults and one in children, with no sample size given for the remission comparison; associations between baseline bacteria and later remission are correlational and need prospective validation.Study · Crohns Colitis 360