Pain vs. Soreness: Reading the Signals

During the run

For the pain you run with, Runsense uses a physical therapist's rule for returning runners. Your clinician may set a different limit.

• Pain stays at 3 out of 10 or lower (4 at most) while you run, and is stable or improving over the weeks.
• Stop the run if it climbs above that.
• It is back to its usual level within 24 hours of finishing. If it is not, the run was too much for now.
• A limp, or any change in how you move, is a stop at any pain level.
• If you need pain medication to run, do not run.

Pain that is a stop at any number

Some pain does not go on the 10-point scale. Sharp pain you can cover with one finger over a bone, pain that is there at rest or at night, and pain that gets worse the longer you run are reasons to stop and have it assessed, whatever the number. Do not wait for a spot you can press to confirm it: in a 2022 study of 50 people with tibial pain, tenderness to palpation picked up 48.6% of the tibial stress fractures found on bone scan, so a painful shin that is not tender when pressed can still be a bone injury¹. The guide on stress fractures covers what happens next.

The next day or two

Delayed-onset muscle soreness (DOMS) is a dull ache in the muscles that did the work, felt when you press them, tighten them or stretch them. Lengthening work sets it off, such as a downhill, a long run after a layoff or a new strength routine, and it arrives after the effort and not during it. It starts within about a day, peaks between 24 and 72 hours and fades over 5 to 7 days, as a 2019 review and a 2025 analysis describe²³.

Keep moving, easily. A 2003 review of treatments found exercise the most effective way to ease soreness, though the relief was temporary, and it suggested cutting the intensity and duration of your running for 1 to 2 days after a session that causes intense soreness⁴. Do not spend money on a fix. In a 2025 network meta-analysis of physical therapies for DOMS, cold therapy, electrical stimulation, ultrasound and soft-tissue work did no better than placebo, light therapy and sauna beat placebo only in the first 48 hours, and nothing beat it at 72 hours. The trials were small and of mixed quality³.

Soreness fades before the muscle has regained its full function, as a 2019 review shows². A leg that no longer aches is not yet ready for a hard session, so keep the next run easy.

By the end of the week

Soreness is gone within about a week. A pain that is sharp or pinpoint, sits over a bone or tendon, gets worse as you run, or has not faded by the end of the week is an injury to ease the load for, not soreness to run through.

A pain that eases once you are warm can still be an injury. In Achilles tendinopathy, a 2023 review reports, the pain sits 2 to 6 centimeters above where the tendon meets the heel bone, runners feel it at the start and end of a run with less in between, and morning stiffness tracks severity⁵. The guide on Achilles tendinopathy covers what to do.

Researchers who study running injuries agreed in 2015 on one mark: running-related pain in the lower limbs that restricts or stops running for at least 7 days or 3 consecutive scheduled sessions, or that sends the runner to a health professional, counts as an injury⁶. Use the same mark. A pain that has cost you a week, or three runs in a row, is not soreness, and it should be assessed.

Flat legs with no pain

A slump can be a signal without any ache. A few flat days after hard training are expected and pass. If heavy legs, falling performance and low mood last while training and recovery stay out of balance, ease the load and see a clinician. A 2013 joint consensus statement of two sports-science colleges says telling nonfunctional overreaching from overtraining syndrome is very difficult, that infection, too little energy, carbohydrate or protein, iron deficiency and allergies have to be excluded first, and that no single hormonal, performance, psychological or blood marker is generally accepted for detecting it⁷. The guide on overtraining covers what to change.