Strength training
Pooled cohorts link muscle-strengthening activity to 15% to 21% fewer deaths and less type 2 diabetes, a J shape with the lowest death risk near 30 to 60 minutes a week. In trials, strength training raised strength and lean mass and lowered HbA1c, blood pressure and depression symptoms. Falls fell in programs that added balance work.
Checked 2026-11-13
- Status
- A daily life factor, not a product.
- Also called
- resistance training, weight training, weightlifting, lifting weights, muscle-strengthening activity, resistance exercise, progressive resistance training, PRT, bodyweight exercise, resistance bands, powerlifting, lifting at the gym
- Studied for
- muscle, strength, living longer, heart health, diabetes prevention, blood sugar, blood pressure, bone density, osteoporosis, fewer falls, aging, mood, depression, anxiety, metabolism
Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on
Shown to help8
- StrongLinked to 15% to 21% fewer deaths with muscle-strengthening activity in pooled cohorts, a J shape with the lowest risk at about 30 to 60 minutes a week.
- StrongLinked to 17% less type 2 diabetes with muscle-strengthening activity in pooled cohorts, with most of the drop by 60 minutes a week.
- StrongShown to lower HbA1c by about 0.4% to 0.6% with resistance training in type 2 diabetes in pooled trials, more at high intensity, without a clear fasting glucose change.
- StrongShown to raise muscle strength by a large amount and lean mass by about 1.1 kg in older adults in pooled trials, with small gains in everyday physical function.
- StrongShown to lower resting blood pressure by about 2 to 4.5 mmHg systolic and 3 mmHg diastolic with dynamic resistance training, and more with isometric training, in pooled trials.
- StrongShown to lower depressive symptoms by a moderate amount and anxiety by a small amount in pooled trials, with smaller effects in trials with blinded assessment.
- ModerateLinked to 17% less cardiovascular disease in one meta-analysis of cohorts, with two other reviews finding borderline lower cardiovascular death.
- ModerateShown to raise hip bone density by about 1% with lower-body strength training in postmenopausal women in a Cochrane review, without a measured drop in fractures.
Reported risks3
- ModerateReported in trials: mostly minor muscle and joint complaints such as joint pain and soreness, with serious adverse events rare and poorly recorded.How often is not known
- LimitedLimited evidence: competitive weight-training sports reported about 0.24 to 7.5 injuries per 1,000 hours, mostly strains, tendinitis and sprains of the shoulder, lower back and knee.How often is not known
- LimitedOne small study found blood pressure peaked at a mean 320/250 mmHg during heavy double-leg presses in experienced bodybuilders.How often is not known
What it was studied for, and what was found
Shown to help8
Death from any cause
Linked to 15% to 21% fewer deaths with muscle-strengthening activity in pooled cohorts, a J shape with the lowest risk at about 30 to 60 minutes a week.
Compared with people doing no muscle-strengthening activity [1]; no exercise [2]; no resistance training [3]
The numbers and sources
- Effect
- Muscle-strengthening activity was linked to 15% lower mortality (RR 0.85, 95% CI 0.79 to 0.93). The dose-response curve was J-shaped, lowest at 40 minutes a week (RR 0.83), with estimates below 1 up to about 140 minutes a week. Combined with aerobic activity, risk was lower still [1]. A second review found 21% lower mortality (HR 0.79, 95% CI 0.69 to 0.91), and 40% lower when combined with aerobic exercise (HR 0.60) [2]. A third found 15% lower mortality (RR 0.85, 95% CI 0.77 to 0.93), with the largest drop, 27%, at about 60 minutes a week, and smaller drops at higher volumes [3].
- Population
- 263,058 adults with 42,133 deaths in 7 cohorts, 236,331 in the dose-response analysis [1]. 370,256 participants in 10 cohorts and 1 trial, mean follow-up 8.85 years [2]. 10 studies of nonclinical adults, 4 in the dose-response analysis [3].
- Sources
- [1], [2], [3]
- Caveats
- Observational, with self-reported activity. Certainty was rated very low and heterogeneity was high (I² 83%) [1]. Few studies informed the dose-response curves, so the shape above 60 minutes a week is uncertain [1][3].
Heart disease
Linked to 17% less cardiovascular disease in one meta-analysis of cohorts, with two other reviews finding borderline lower cardiovascular death.
Compared with people doing no muscle-strengthening activity [1]; no exercise [2]; no resistance training [3]
The numbers and sources
- Effect
- Muscle-strengthening activity was linked to lower cardiovascular disease (RR 0.83, 95% CI 0.73 to 0.93), J-shaped with the largest drop, 18%, at 60 minutes a week [1]. Cardiovascular death had an HR of 0.83 (95% CI 0.67 to 1.03) in one review [2] and an RR of 0.81 (95% CI 0.66 to 1.00) in another [3].
- Population
- 257,888 adults with 16,056 cases in 7 cohorts [1]. 11 studies [2]. 4 studies for cardiovascular death [3].
- Sources
- [1], [2], [3]
- Caveats
- Observational. Two of three estimates had intervals reaching no difference, and certainty was rated very low [1].
Type 2 diabetes
Linked to 17% less type 2 diabetes with muscle-strengthening activity in pooled cohorts, with most of the drop by 60 minutes a week.
Compared with people doing no muscle-strengthening activity [1]; lower amounts of resistance exercise [4]; men doing no weight training [5]
The numbers and sources
- Effect
- Muscle-strengthening activity was linked to lower diabetes risk (RR 0.83, 95% CI 0.77 to 0.89), an L shape with a large drop up to 60 minutes a week [1]. A second review found an inverse, nonlinear link between resistance exercise and diabetes [4]. In US men, 150 minutes a week or more of weight training was linked to 34% lower risk (95% CI 7% to 54%), and combined with the same amount of aerobic exercise to 59% lower [5].
- Population
- 202,486 adults with 9,548 cases in 5 cohorts [1]. 81 studies [4]. 32,002 men followed 18 years, with 2,278 cases [5].
- Sources
- [1], [4], [5]
- Caveats
- Observational. Certainty was rated low [1]. People who lift weights may differ in diet and body weight.
HbA1c and fasting glucose in type 2 diabetes
Shown to lower HbA1c by about 0.4% to 0.6% with resistance training in type 2 diabetes in pooled trials, more at high intensity, without a clear fasting glucose change.
Compared with control groups in randomized trials [6][7][8]; aerobic training [6]
The numbers and sources
- Effect
- Resistance training lowered HbA1c by 0.39% against controls (95% CI -0.60 to -0.18), more when strength rose more, and did not differ from aerobic training [6]. High-intensity training lowered HbA1c by 0.61% and low to moderate intensity by 0.23%. Fasting blood glucose fell only as a nonsignificant trend across 15 trials [7]. A third review found a 0.57% fall (95% CI -1.14% to -0.01%) [8].
- Population
- 1,172 adults with type 2 diabetes in 20 trials [6]. 962 patients in 24 trials, 443 in the fasting glucose analysis [7]. Patients with type 2 diabetes in trials of at least 12 weeks [8].
- Sources
- [6], [7], [8]
- Caveats
- Heterogeneity was high (I² 69.2% [6], 92.5% [8]).
Muscle strength, lean mass and physical function
Shown to raise muscle strength by a large amount and lean mass by about 1.1 kg in older adults in pooled trials, with small gains in everyday physical function.
Compared with control groups in randomized trials [9]; before training, in the same people, in randomized and nonrandomized studies [10][11]
The numbers and sources
- Effect
- Progressive resistance training had a large effect on strength (SMD 0.84, 95% CI 0.67 to 1.00, 73 trials), a small effect on physical ability (SMD 0.14), a gait speed gain of 0.08 m/s and a moderate to large effect on rising from a chair (SMD -0.94) [9]. Strength rose 29% in leg press, 24% in chest press, 33% in knee extension and 25% in lat pull, more with higher intensity [10]. Lean body mass rose 1.1 kg (95% CI 0.9 to 1.2), more with higher volume and less in older participants [11].
- Population
- 6,700 older adults in 121 trials, mostly training 2 to 3 times a week at high intensity [9]. 1,079 adults 50 and older in 47 studies [10]. 1,328 adults 50 and older in 49 studies [11].
- Sources
- [9], [10], [11]
- Caveats
- Heterogeneity was high (I² 84% for lean mass) [11]. The two strength and lean mass reviews included nonrandomized studies and before-and-after changes [10][11].
Blood pressure
Shown to lower resting blood pressure by about 2 to 4.5 mmHg systolic and 3 mmHg diastolic with dynamic resistance training, and more with isometric training, in pooled trials.
Compared with non-exercising control groups [12][13]
The numbers and sources
- Effect
- Dynamic resistance training lowered blood pressure by 1.8/3.2 mmHg, most in people with prehypertension (4.0/3.8 mmHg). Isometric resistance training lowered it by 10.9/6.2 mmHg in a few studies [12]. A larger analysis found 4.55/3.04 mmHg with dynamic resistance training and 8.24/4.00 mmHg with isometric training [13].
- Population
- 29 dynamic and 5 isometric resistance groups among 5,223 adults in 93 trials [12]. 15,827 participants in 270 trials [13].
- Sources
- [12], [13]
- Caveats
- Trials lasted weeks to months. The isometric estimates rest on far fewer trials [12].
Bone density
Shown to raise hip bone density by about 1% with lower-body strength training in postmenopausal women in a Cochrane review, without a measured drop in fractures.
Compared with control groups in randomized trials [14]; a home-based low-intensity exercise program [15]
The numbers and sources
- Effect
- Progressive resistance training for the legs raised femoral neck bone density by 1.03% (95% CI 0.24 to 1.82) against controls. Combination programs raised spine density by 3.22%. Fractures did not differ (OR 0.61, 95% CI 0.23 to 1.64) [14]. In women with low bone mass, 8 months of supervised high-intensity resistance and impact training changed lumbar spine density by 2.9% against -1.2%, and femoral neck density by 0.3% against -1.9% [15].
- Population
- 4,320 postmenopausal women in 43 trials [14]. 101 postmenopausal women with low bone mass, aged about 65 [15].
- Sources
- [14], [15]
- Caveats
- Reporting quality in the trials was low [14]. The fracture analysis was small, and the high-intensity trial was one small study with close supervision [15].
Depression and anxiety symptoms
Shown to lower depressive symptoms by a moderate amount and anxiety by a small amount in pooled trials, with smaller effects in trials with blinded assessment.
Compared with nonactive control conditions [17][18]; active controls such as usual care or a placebo tablet [19]
The numbers and sources
- Effect
- Resistance training reduced depressive symptoms (effect size 0.66, 95% CI 0.48 to 0.83), a number needed to treat of 4, regardless of health status or training volume [17]. It reduced anxiety symptoms (effect size 0.31, 95% CI 0.17 to 0.44), more in healthy people (0.50) [18]. In major depression, strength training reduced symptoms (g -0.49, 95% credible interval -0.69 to -0.29) and was among the options people tolerated most [19].
- Population
- 1,877 participants in 33 trials [17]. 922 participants in 16 trials [18]. 643 people with major depression in 22 strength training arms [19].
- Sources
- [17], [18], [19]
- Caveats
- Trials with blinded allocation or assessment found smaller effects [17]. Confidence in the depression network results was rated very low for strength training [19].
Mixed results1
Falls in older adults
Mixed results: programs combining balance and strength exercises probably cut falls by about a third, while the effect of strength training alone was uncertain.
Compared with control interventions not thought to reduce falls [16]
The numbers and sources
- Effect
- Programs with several exercise types, most often balance and functional exercises plus resistance exercises, probably reduced the rate of falls by 34% (RaR 0.66, 95% CI 0.50 to 0.88) and the number of people falling by 22% (RR 0.78). Balance and functional exercises reduced the rate of falls by 24%. The review was uncertain of the effect of programs that were mainly resistance training [16].
- Population
- 23,407 people 60 and older living in the community, average age 76, in 108 trials [16].
- Sources
- [16]
- Caveats
- Evidence for mixed programs was rated moderate in certainty, and for resistance training alone too uncertain to judge [16].
Amounts studied
The WHO 2020 guidelines set muscle-strengthening activity at moderate or greater intensity, involving all major muscle groups, on 2 or more days a week. They found no evidence of a dose-response with higher volumes [20]. Cohorts measured minutes a week. The lowest death risk was at about 30 to 60 minutes a week [1][3], and diabetes risk dropped most up to 60 minutes a week [1]. One cohort studied 150 minutes a week or more of weight training [5].
Trials in older adults mostly trained 2 to 3 times a week at high intensity [9]. High intensity in the diabetes review meant 75% to 100% of the one-repetition maximum [7]. The bone trial used two 30-minute supervised sessions a week of 5 sets of 5 repetitions above 85% of the one-repetition maximum, for 8 months [15].
Risks
Reported risks3
Muscle and joint complaints in trials
Reported in trials: mostly minor muscle and joint complaints such as joint pain and soreness, with serious adverse events rare and poorly recorded.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- Across 121 trials in older adults, adverse events were poorly recorded. Joint pain and muscle soreness were reported in many trials that monitored them, serious adverse events were rare, and none was reported as directly related to training [9]. In falls prevention trials, reported events were mainly non-serious and musculoskeletal, with two serious events, a pelvic stress fracture and hernia surgery, in one trial [16]. The high-intensity bone trial recorded one minor back spasm [15].
- Population
- 6,700 older adults in 121 trials [9]. 6,019 participants in 27 trials that reported adverse events [16]. 101 postmenopausal women [15].
- Sources
- [9], [16], [15]
- Caveats
- Most trials did not monitor adverse events closely in both groups, so rates cannot be given [9][16].
Injuries in weight-training sports
Limited evidence: competitive weight-training sports reported about 0.24 to 7.5 injuries per 1,000 hours, mostly strains, tendinitis and sprains of the shoulder, lower back and knee.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- Bodybuilding had the lowest rates, 0.24 to 1 injury per 1,000 hours. Strongman had 4.5 to 6.1 and Highland Games 7.5. The shoulder, lower back, knee, elbow and wrist or hand were most often injured [21].
- Population
- Competitive athletes in weightlifting, powerlifting, bodybuilding, strongman, Highland Games and CrossFit, in 20 studies [21].
- Sources
- [21]
- Caveats
- Most studies were retrospective and only 5 of 20 had a low risk of bias. These are competitive athletes, not people training for health [21].
Very high blood pressure during heavy lifts
One small study found blood pressure peaked at a mean 320/250 mmHg during heavy double-leg presses in experienced bodybuilders.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- Measured directly in the artery, pressure rose to a group mean of 320/250 mmHg during double-leg presses to failure, above 480/350 mmHg in one lifter, and 255/190 mmHg during single-arm curls. Breath-holding against a closed airway contributed part of the rise [22].
- Population
- 5 experienced bodybuilders lifting at 80% to 100% of their maximum [22].
- Sources
- [22]
- Caveats
- Five people in one 1985 study. Pressures fell quickly after each lift, and the study did not measure any later harm.
Claims tested and not found
- That more strength training always brings more longevity. Death risk was lowest at about 40 to 60 minutes a week, and estimates stayed below no difference only up to about 130 to 140 minutes a week [1][3].
- That strength training alone prevents falls in older people. The Cochrane review was uncertain of the effect of programs that were mainly resistance training [16].
- That aerobic exercise lowers HbA1c more than strength training in type 2 diabetes. Pooled trials found no significant difference between the two [6].
- That heavy lifting injures women with low bone mass. In 8 months of supervised high-intensity training, the only adverse event was a minor back spasm [15].
Related
Sources
- Momma H, Kawakami R, Honda T, Sawada SS. Muscle-strengthening activities are associated with lower risk and mortality in major non-communicable diseases: a systematic review and meta-analysis of cohort studies. British Journal of Sports Medicine. 2022. https://doi.org/10.1136/bjsports-2021-105061
- Saeidifard F, Medina-Inojosa JR, West CP, et al. The association of resistance training with mortality: A systematic review and meta-analysis. European Journal of Preventive Cardiology. 2019. https://doi.org/10.1177/2047487319850718
- Shailendra P, Baldock KL, Li LSK, Bennie JA, Boyle T. Resistance Training and Mortality Risk: A Systematic Review and Meta-Analysis. American Journal of Preventive Medicine. 2022. https://doi.org/10.1016/j.amepre.2022.03.020
- Aune D, Norat T, Leitzmann M, Tonstad S, Vatten LJ. Physical activity and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis. European Journal of Epidemiology. 2015. https://doi.org/10.1007/s10654-015-0056-z
- Grøntved A, Rimm EB, Willett WC, Andersen LB, Hu FB. A prospective study of weight training and risk of type 2 diabetes mellitus in men. Archives of Internal Medicine. 2012. https://doi.org/10.1001/archinternmed.2012.3138
- Jansson AK, Chan LX, Lubans DR, Duncan MJ, Plotnikoff RC. Effect of resistance training on HbA1c in adults with type 2 diabetes mellitus and the moderating effect of changes in muscular strength: a systematic review and meta-analysis. BMJ Open Diabetes Research and Care. 2022. https://doi.org/10.1136/bmjdrc-2021-002595
- Liu Y, Ye W, Chen Q, et al. Resistance Exercise Intensity is Correlated with Attenuation of HbA1c and Insulin in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis. International Journal of Environmental Research and Public Health. 2019. https://doi.org/10.3390/ijerph16010140
- Umpierre D, Ribeiro PA, Kramer CK, et al. Physical activity advice only or structured exercise training and association with HbA1c levels in type 2 diabetes: a systematic review and meta-analysis. JAMA. 2011. https://doi.org/10.1001/jama.2011.576
- Liu CJ, Latham NK. Progressive resistance strength training for improving physical function in older adults. Cochrane Database of Systematic Reviews. 2009. https://doi.org/10.1002/14651858.CD002759.pub2
- Peterson MD, Rhea MR, Sen A, Gordon PM. Resistance exercise for muscular strength in older adults: a meta-analysis. Ageing Research Reviews. 2010. https://doi.org/10.1016/j.arr.2010.03.004
- Peterson MD, Sen A, Gordon PM. Influence of resistance exercise on lean body mass in aging adults: a meta-analysis. Medicine and Science in Sports and Exercise. 2011. https://doi.org/10.1249/MSS.0b013e3181eb6265
- Cornelissen VA, Smart NA. Exercise training for blood pressure: a systematic review and meta-analysis. Journal of the American Heart Association. 2013. https://doi.org/10.1161/JAHA.112.004473
- Edwards JJ, Deenmamode AHP, Griffiths M, et al. Exercise training and resting blood pressure: a large-scale pairwise and network meta-analysis of randomised controlled trials. British Journal of Sports Medicine. 2023. https://doi.org/10.1136/bjsports-2022-106503
- Howe TE, Shea B, Dawson LJ, et al. Exercise for preventing and treating osteoporosis in postmenopausal women. Cochrane Database of Systematic Reviews. 2011. https://doi.org/10.1002/14651858.CD000333.pub2
- Watson SL, Weeks BK, Weis LJ, et al. High-Intensity Resistance and Impact Training Improves Bone Mineral Density and Physical Function in Postmenopausal Women With Osteopenia and Osteoporosis: The LIFTMOR Randomized Controlled Trial. Journal of Bone and Mineral Research. 2018. https://doi.org/10.1002/jbmr.3284
- Sherrington C, Fairhall NJ, Wallbank GK, et al. Exercise for preventing falls in older people living in the community. Cochrane Database of Systematic Reviews. 2019. https://doi.org/10.1002/14651858.CD012424.pub2
- Gordon BR, McDowell CP, Hallgren M, et al. Association of Efficacy of Resistance Exercise Training With Depressive Symptoms: Meta-analysis and Meta-regression Analysis of Randomized Clinical Trials. JAMA Psychiatry. 2018. https://doi.org/10.1001/jamapsychiatry.2018.0572
- Gordon BR, McDowell CP, Lyons M, Herring MP. The Effects of Resistance Exercise Training on Anxiety: A Meta-Analysis and Meta-Regression Analysis of Randomized Controlled Trials. Sports Medicine. 2017. https://doi.org/10.1007/s40279-017-0769-0
- Noetel M, Sanders T, Gallardo-Gómez D, et al. Effect of exercise for depression: systematic review and network meta-analysis of randomised controlled trials. BMJ. 2024. https://doi.org/10.1136/bmj-2023-075847
- Bull FC, Al-Ansari SS, Biddle S, et al. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. British Journal of Sports Medicine. 2020. https://doi.org/10.1136/bjsports-2020-102955
- Keogh JW, Winwood PW. The Epidemiology of Injuries Across the Weight-Training Sports. Sports Medicine. 2017. https://doi.org/10.1007/s40279-016-0575-0
- MacDougall JD, Tuxen D, Sale DG, Moroz JR, Sutton JR. Arterial blood pressure response to heavy resistance exercise. Journal of Applied Physiology. 1985. https://doi.org/10.1152/jappl.1985.58.3.785