A warm-up is the preparation between arriving at training and your first working effort. It raises muscle temperature, brings heart rate and breathing up gradually, and rehearses the movements the session will use. Warm-up sets are the strength-training part of it, lighter sets of a lift performed before your working weight, each one heavier than the last.
Most warm-ups are either too short to change anything or so long that they tire you before the real work starts. The research gives useful limits for both. Fradkin and colleagues' 2010 meta-analysis in the Journal of Strength and Conditioning Research found that warming up improved performance in 79% of the outcomes examined across 32 high-quality studies, with little evidence that it ever hurt. This entry covers what a warm-up changes in your body, how long and how hard to make it, where stretching fits, how to build warm-up sets for heavy lifting, and what injury-prevention warm-ups have shown.
01What a warm-up changes
Temperature has the largest effect. Racinais and Oksa's 2010 review in the Scandinavian Journal of Medicine and Science in Sports reports that short-duration performance improves by 2% to 5% for each 1 °C rise in muscle temperature. They trace the effect to faster transmission of the nerve signal to the muscle and to changes in excitation-contraction coupling, the step that turns that signal into force. The benefit holds only while your core temperature stays normal. Once you become hyperthermic, performance falls, so a long, hard warm-up before a race on a hot day can cost you.
McGowan and colleagues' 2015 review in Sports Medicine describes the other effects of an active warm-up. Oxygen uptake responds faster once the main effort begins, anaerobic metabolism increases, and neural and psychological readiness improve. Passive heating, such as heated garments, raises temperature without spending energy, which makes it useful for staying warm in the gap between the warm-up and the start of competition.
Heavy or explosive efforts near the end of a warm-up add one more effect. Blazevich and Babault's 2019 review in Frontiers in Physiology separates two phenomena that are often confused. Post-activation potentiation (PAP) is a short-lived increase in muscle force with a half-life of about 28 seconds. Post-activation performance enhancement (PAPE) is the improvement in voluntary force, jumping or sprinting seen several minutes after intense contractions, and it depends on muscle temperature, muscle water content and activation. PAPE is the effect you can use in practice. It is why a few heavy singles or short sprints late in a warm-up can make your first working set feel sharper, as long as enough rest follows.
02How long and how hard
Silva and colleagues' 2018 systematic review in Sports Medicine analyzed 30 studies of warm-ups before explosive efforts in team sports. Five minutes of jogging followed by 7 minutes of dynamic exercises improved sprint times by 7.69%, jump performance by 8.61% and agility times by 6.65%. The studies tended to recommend a short active warm-up of 10 to 15 minutes, with intensity rising gradually from about 50% to 90% of maximum heart rate.
What you do after the warm-up counts too. The benefits in Silva's review came with 2 to 10 minutes of passive rest before the main effort. When the transition ran longer than 15 minutes, a 2-minute re-warm-up of short sprints and jumps at about 90% of maximum heart rate was the most effective strategy. If you warm up and then spend 20 minutes talking or setting up equipment, you have lost much of what you built.
Endurance sessions follow the same logic at lower intensity. The opening minutes of an easy run or ride at zone 2 effort are the general warm-up. Before intervals or a race, add a few short efforts at or above target pace so your oxygen uptake is already elevated when the hard work begins. Silva's 10 to 15 minutes is a reasonable starting point for the total.
03Where stretching fits
Behm and colleagues open their 2016 review in Applied Physiology, Nutrition, and Metabolism by noting the shift in warm-ups from static stretching toward dynamic stretching. Their data explain why. Static stretching reduced performance by 3.7% on average, and dynamic stretching improved it by 1.3%. The length of each hold decided the cost. Holds of 60 seconds or more per muscle group reduced performance by 4.6%, and holds under 60 seconds by 1.1%. Most studies tested performance 3 to 5 minutes after stretching with nothing in between, and when dynamic activity followed the stretching, no clear performance effect remained. Kay and Blazevich (2012) found no detrimental effect from static stretches shorter than 30 seconds.
Short static holds on a joint that limits the session's positions therefore do no harm when dynamic movement follows them. Long holds belong after training. The dynamic stretching, static stretching and mobility entries cover each method in detail.
04Warm-up sets for strength training
Warm-up sets rehearse the exact lift at loads that climb toward your working weight. They let you settle the bar path, feel how the load moves today, and reach the heavy sets without a jump your body has not prepared for.
A standard ramp for heavy work
Brown and Weir's 2001 procedures for the American Society of Exercise Physiologists give a well-defined ramp for one-repetition maximum (1RM) testing. After 3 to 5 minutes of light general activity for the muscles being tested, you perform 8 repetitions at about 50% of your estimated 1RM, then 3 repetitions at about 70%. Single repetitions of increasing weight follow, with at least two singles between the triple and your estimated maximum. Rest 1 to 5 minutes between sets. They put the optimal number of heavy singles at three to five.
| Step | Load | Repetitions | Purpose |
|---|---|---|---|
| General warm-up | Light activity for the working muscles | 3 to 5 min | Raise muscle temperature |
| Warm-up set 1 | About 50% of estimated 1RM | 8 | Rehearse the movement |
| Warm-up set 2 | About 70% of estimated 1RM | 3 | Approach working bar speed |
| Singles | Evenly spaced increases, at least two of them | 1 each | Calibrate the load and prime the lift |
Protocol from Brown and Weir (2001), with 1 to 5 minutes of rest between sets.
For a lifter with an estimated squat maximum of 150 kg, the ramp is 8 repetitions at 75 kg and 3 at 105 kg, then singles at evenly spaced loads such as 120 kg and 135 kg before an attempt at 150 kg. For a heavy set of three or five, you can keep the same shape and stop the singles below the working weight.
Heavier warm-ups help near-maximal work
Ribeiro and colleagues' 2021 systematic review in Motricidade concluded that maximal strength and repetitions "could be positively affected when a specific warm-up is performed at loads close to the maximum." The main improvements appeared with 3 to 10 minutes of rest between the warm-up and the test. Ribeiro's group then compared three specific warm-ups in 40 resistance-trained men lifting 3 sets of 6 repetitions at 80% of 1RM (International Journal of Environmental Research and Public Health, 2020). In the squat, a warm-up set of 6 repetitions at 80% of the training load produced faster bar speeds in later sets than 6 repetitions at 40%. In the bench press, a two-step warm-up at 40% and then 80% of the training load gave the most total work, 4,750 J against 4,632 J after the light warm-up alone.
Moderate loads may need less
Warm-up sets matter less when the working load is moderate. Enes and colleagues (Sports Medicine and Health Science, 2025) had 29 trained lifters perform 4 sets to failure at their 10-repetition maximum on the bench press and leg press. Beforehand they did no specific warm-up, one set of 3 to 4 repetitions at 75% of their 10RM load, or two sets at 55% and 75%. The warm-ups made negligible to small differences in repetitions, fatigue, training volume and perceived effort. The authors suggest you can save time by skipping the specific warm-up "when training at ~10RM loads."
Taken together, the case for warm-up sets grows with load and technical difficulty. Before a heavy single, a competition lift or a fast technical lift such as a snatch, build a full ramp. Before sets of 10 or more repetitions, especially on the third or fourth exercise of a session when you are already warm, one light set or none is reasonable.
Warm-up sets as a readiness check
Warm-up sets also show you how the session is likely to go. If a load that usually moves quickly feels slow or heavy, adjust before the working sets. Add an intermediate step, or lower the target and let RPE guide the working sets. The auto-regulation entry covers rules for making these calls consistently.
05Warm-ups that prevent injuries
Warm-up programs built around strength, balance and landing practice have the strongest injury evidence. Soligard and colleagues' cluster randomized trial in the BMJ (2008) followed 1,892 female football players aged 13 to 17 in 125 Norwegian clubs for a season. The program took about 20 minutes, with running exercises, strength, plyometric and balance work such as Nordic hamstring lowers and single-leg balance, and a short block of football-specific running. The primary outcome, lower-extremity injuries, fell with a rate ratio of 0.71, which did not reach statistical significance. Overall injuries fell with a rate ratio of 0.68, severe injuries 0.55 and overuse injuries 0.47. Thorborg and colleagues' 2017 meta-analysis in the British Journal of Sports Medicine pooled 4 studies of the same program, known as FIFA 11+, and estimated that it reduced football injuries by 39%.
Jogging and stretching on their own have much weaker support. Behm et al. (2016) found that static stretching and contract-relax (PNF) stretching had no clear effect on all-cause or overuse injuries. Brown and Weir wrote in 2001 that "there is little data directly supporting decreased injury risk associated with warm up activities." If injury risk is your concern, put strength and landing work into your warm-up time. The injury prevention entry covers the wider evidence.
06Matching the warm-up to the session
| Session | General part | Specific part |
|---|---|---|
| Heavy strength | 3 to 5 min of light activity | Ramp of warm-up sets with singles near the working weight |
| Hypertrophy at 10RM or lighter | A few minutes of light movement | One light set, or none after the first exercise |
| Sprints, jumps and team sports | 5 min of jogging | 7 min of dynamic drills, then short sprints and jumps |
| Intervals or a race | Easy aerobic work | A few short efforts at or above target pace |
| Easy aerobic session | The opening minutes at easy pace | None |
Heavy strength from Brown and Weir (2001), hypertrophy from Enes et al. (2025), sprints and team sports from Silva et al. (2018).
07Common mistakes
A warm-up that tires you. Several sets of 10 or more repetitions before a heavy lift spend energy you need for the working sets. Cut repetitions as the load rises, as the 8-then-3 pattern in the ramp above does.
A long wait after warming up. Past 15 minutes of standing around, much of the benefit has faded (Silva et al., 2018). Warm up again with 2 minutes of short sprints or jumps, or a light set of your first lift.
Long static holds before power work. Keep pre-training holds under 60 seconds per muscle, ideally under 30, and follow them with movement.
Big jumps to the working weight. Going from a light set straight to a near-maximal load skips the rehearsal that heavier warm-up sets provide. Add intermediate steps as the load climbs.
One warm-up for every session. A sprint session, a heavy squat day and an easy run each need different preparation.
08References
- Behm DG et al. (2016). Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals, a systematic review. Applied Physiology, Nutrition, and Metabolism 41(1):1-11. https://doi.org/10.1139/apnm-2015-0235
- Blazevich AJ et al. (2019). Post-activation potentiation versus post-activation performance enhancement in humans, historical perspective, underlying mechanisms, and current issues. Frontiers in Physiology 10:1359. https://doi.org/10.3389/fphys.2019.01359
- Brown LE et al. (2001). ASEP procedures recommendation I, accurate assessment of muscular strength and power. Journal of Exercise Physiology Online 4(3):1-21. https://www.asep.org/asep/asep/Brown2.pdf
- Enes A et al. (2025). Warming up to improved performance? Effects of different specific warm-up protocols on neuromuscular performance in trained individuals. Sports Medicine and Health Science. https://doi.org/10.1016/j.smhs.2025.08.002
- Fradkin AJ et al. (2010). Effects of warming-up on physical performance, a systematic review with meta-analysis. Journal of Strength and Conditioning Research 24(1):140-148. https://doi.org/10.1519/JSC.0b013e3181c643a0
- Kay AD et al. (2012). Effect of acute static stretch on maximal muscle performance, a systematic review. Medicine and Science in Sports and Exercise 44(1):154-164. https://doi.org/10.1249/MSS.0b013e318225cb27
- McGowan CJ et al. (2015). Warm-up strategies for sport and exercise, mechanisms and applications. Sports Medicine 45(11):1523-1546. https://doi.org/10.1007/s40279-015-0376-x
- Racinais S et al. (2010). Temperature and neuromuscular function. Scandinavian Journal of Medicine and Science in Sports 20(Suppl 3):1-18. https://doi.org/10.1111/j.1600-0838.2010.01204.x
- Ribeiro B et al. (2020). The role of specific warm-up during bench press and squat exercises, a novel approach. International Journal of Environmental Research and Public Health 17(18):6882. https://doi.org/10.3390/ijerph17186882
- Ribeiro B et al. (2021). The effect of warm-up in resistance training and strength performance, a systematic review. Motricidade 17(1):87-94. https://doi.org/10.6063/motricidade.21143
- Silva LM et al. (2018). Effects of warm-up, post-warm-up, and re-warm-up strategies on explosive efforts in team sports, a systematic review. Sports Medicine 48(10):2285-2299. https://doi.org/10.1007/s40279-018-0958-5
- Soligard T et al. (2008). Comprehensive warm-up programme to prevent injuries in young female footballers, cluster randomised controlled trial. BMJ 337:a2469. https://doi.org/10.1136/bmj.a2469
- Thorborg K et al. (2017). Effect of specific exercise-based football injury prevention programmes on the overall injury rate in football, a systematic review and meta-analysis of the FIFA 11 and 11+ programmes. British Journal of Sports Medicine 51(7):562-571. https://doi.org/10.1136/bjsports-2016-097066
