No pain, no gain? Jeremy Ethier on soreness and effort

"No pain, no gain" isn't a good rule for building a routine. Soreness the next day mostly means your muscles weren't used to the work, and it doesn't show the session counted. For most sessions, aim for a moderate pace where you can talk but not sing, finish feeling you could do a little more, and stop if anything hurts or you feel unwell.

The slogan sounds like honesty about effort, and it makes the next session harder to face. Ethier, whose channel is about lifting and building muscle, made a video for lifters who stop getting sore and decide their training has stopped working. The video opens on the belief Ethier hears from lifters: the sorer you are after a workout, the more your muscles will grow (Built With Science). The video has been watched more than 1.3 million times. Ethier is a creator, not a researcher, and the video's frame is muscle growth; its central point, though, matches what exercise scientists write about soreness.

I-Min Lee, a professor of epidemiology at Harvard, used to believe the slogan too. "When I was younger, I suppose, because I was also more physically capable, I sort of strongly believed in that no pain, no gain," Lee told the Viva Longevity channel (Viva Longevity, 9:30). The data changed Lee's mind.

Below are seven steps in three parts: where the slogan came from, how to find a pace that brings you back, and when to stop. The grouping is ours.

Where "no pain, no gain" came from

1. Know whose rule it was

"So, when I started in the field, the philosophy was sort of no pain, no gain," Lee says (8:13). "You needed to exercise vigorously, you needed to do your physical activity in a continuous bout before you got health benefits." Lee traces the rule to who was studied. Early researchers were mostly exercise physiologists interested in fitness, and their volunteers tended to be graduate students. "So the graduate students at that time were mainly young men. Young men were already fit" (8:49). To make them fitter, the training had to be hard.

Studies of the general population came later and told a different story. "You could be physically active at a moderate intensity level. Walking is just as good," Lee says (9:11 to 9:16). The rule was built for one group with one goal. If your goal is a routine that lasts, it was never written for you.

Marie Murphy, Professor of Exercise and Health at Ulster University, sees the cost of the slogan in people who don't like exercise. On BBC Radio 4's Just One Thing, Murphy said exercise "has been sold to us as being hard, being a punishment," and "it's seen as a negative punishment, no pain, no gain sort of thing. Whereas I think if you reframe that and you think of how good it makes you feel, then it's something you look forward to doing rather than live in dread of doing" (BBC Radio 4, about 3:09 to 3:20).

2. Read soreness for what it is

Ethier's conclusion is plain: "Muscle soreness does not indicate muscle growth" (3:05). Ethier's examples: some muscles, like the shoulders, rarely get as sore as the legs and still grow, and long-distance running often leaves people sore without building much muscle. And if you stop getting sore, "it's not a big deal if you're still progressing with your exercises throughout the weeks" (3:28).

Three researchers at Liverpool John Moores University put the same point for everyone, not only lifters. Soreness in the hours or days after exercise "typically" happens "after we've done particularly strenuous exercise, or if we do exercise we aren't used to," and "it usually peaks about two days later," depending on how hard and how much you did. Being sore "doesn't necessarily mean you've had a more effective session," they write; "it just means you're doing something your muscles aren't used to" (Langan-Evans, Clark & Erskine, 2022). People who exercise regularly tend to get less of it, because the muscles adapt.

In practice: your first week of brisk walks leaves your calves stiff on day two, which is common with new work and tends to ease within days. By week three the same route leaves you feeling fine. Your muscles are used to it now, and the sessions still count.

Find the pace that brings you back

3. Use the talk test

The simplest guide to effort needs no gadget. "One way to tell if you're working at a moderate intensity level is if you can still talk, but not sing," says the NHS. At a vigorous level, "you will not be able to say more than a few words without pausing for breath" (NHS, 2024).

The CDC adds a scale. On 0 to 10, where 0 is sitting and 10 is maximal effort, moderate is "a level of effort of 5 or 6," and vigorous "begins at a 7 or 8" (CDC, 2025). It's your own scale. As the UK guidelines note, intensity is "relative to an individual's fitness," so the same walk can be light for one person and vigorous for another (UK Chief Medical Officers, 2019).

For the first weeks of a new routine, keep most sessions at the talking pace. If you can sing, you can go a little brisker; if you can only manage a few words, ease off.

4. Let the feeling choose the pace

How a session feels seems to shape whether there's a next one. A 2020 review of research on feelings and physical activity found "a positive association between more positively valenced affective responses during PA and future PA behavior": people who felt better while active tended to do more later. Intensity "is perhaps the factor most robustly associated" with how exercise feels, and people who chose their own pace tended to feel better and do more over time than people given a fixed target (Stevens et al., 2020).

One small study shows how much people differ. Researchers put 37 inactive adults through a moderate session on a treadmill. About a quarter (27%) felt better as they reached a moderate pace, about three in ten (29.7%) felt worse, and the rest felt about the same. How good they felt predicted how active they were six and twelve months later, though the link was weaker once the researchers allowed for how hard the work felt to them (Williams et al., 2008). It's a link in a small group, not proof, and it points the same way as the review: if moderate feels bad to you, go a notch lighter.

Two habits help: finish while you could still do a little more, and at the end, notice one thing you feel better about. If sessions have felt like a chore, our guide to enjoying exercise goes further.

5. Ease in when the work is new

Most next-day soreness comes from doing too much of something new too soon. "If you're starting out a new exercise programme and your first workout is particularly intense or long-lasting, it's pretty difficult to avoid DOMS," the Liverpool researchers write, using the scientific name for delayed onset muscle soreness. For lifters who get too sore, Ethier suggests lowering the volume or intensity at first and easing into it over time (3:20).

US guidance says the same in four words: "start low and go slow." It also links the risk of getting hurt to the size of the jump: the risk "is directly related to the gap between a person's usual level of activity and a new level of activity" (US HHS, 2018). So start with a short version, about ten minutes at a talking pace, and add one thing at a time after two steady weeks. Our guide to short workouts shows why ten minutes counts, and strength training for beginners covers the smallest way into strength.

Know when to stop

6. Stop if anything hurts

Stiffness a day or two after new work is one thing. Pain while you're exercising is another: it's a reason to stop, never a goal to push through. The rule for every session is short: "Stop if anything hurts or you feel unwell." The British Heart Foundation gives the same advice for symptoms: "stop and rest if you notice them during your exercise" (British Heart Foundation, Staying active).

Some things are worth a word with a doctor before you start or step up. Check with a doctor first, then come back to your plan, if you have chest pain, pressure or fainting when you're active; a pounding, skipping or racing heart, dizziness or unusual breathlessness when you're active; a heart, kidney or metabolic condition, or another long-term condition or symptoms you're unsure about; if a doctor has told you to limit your activity; or after recent surgery, a heart event, an injury or an illness. If you're pregnant or recently gave birth, agree your choices with your midwife or doctor. With a cold or fever, wait until you're better.

For everyone else, a doctor's visit isn't required to begin. "The NHS suggests speaking to your GP first if you haven't exercised for a while. WHO and US guidance say that for light to moderate activity, like brisk walking, that's generally not needed. If checking would put your mind at rest, do." And as you do more: if you notice new symptoms, talk to a doctor.

7. Don't make pushing through the point

The slogan's quiet harm is that it turns effort into proof. Some people end up training through pain or illness, or can't skip a day without feeling bad about it. The 1h Protocol to Build an Exercise Routine puts its line this way: "If you're exercising through pain or illness, that's worth talking to a doctor about. So is exercise that feels like something you can't miss without distress."

For a routine that lasts, the sessions that count are the ones you keep doing, and an easy day or a rest day when you feel unwell is part of the plan. Our guide to making exercise a habit explains why counting the week, not the day, takes the pressure off.

Any little thing

Lee's own path runs from the slogan to its opposite. Once the data on ordinary people came in, "what surprised me is that there's almost like no bottom line," Lee says. "So, any little thing you can do is good" (9:39 to 9:45). Ethier gets there from the lifting side: soreness isn't the scorecard. The scorecard is whether you come back.

To build a routine at a pace you'll keep, try the 1h Protocol to Build an Exercise Routine, a program of practical education. Its free first chapter starts with a quick check, asks how your last try ended and finds your pattern, one of five or the Tune-up, with one thing to do tomorrow. The full program takes about an hour: seven chapters show why your last try stopped and what counts, including the talk test, then build one session from your slot to the next, set your short version for hard days and your weekly number with planned skips, and plan the slot after a miss. You leave with up to three changes to start now, your line for the slot after a miss in your own words, a log that records how each session felt and counts the week with planned skips, your slots in your calendar, and reviews on days 7, 14 and 30. Four one-tap check-ins follow by email on days 1, 7, 14 and 30, if you're signed in. Start free

Frequently asked questions

Do I need to be sore for a workout to work?

No. Soreness mostly means your muscles weren't used to the work, and people who train regularly get less of it (Langan-Evans, Clark & Erskine, 2022). "Muscle soreness does not indicate muscle growth," as Jeremy Ethier puts it (Built With Science, 3:05). A session at a talking pace counts.

Is it OK to exercise when I'm still sore?

Stiffness after new work is common, usually peaks about two days after, and tends to ease as your muscles get used to it. Something gentler that day, such as a short easy walk, is a common choice. Whatever you do, stop if anything hurts or you feel unwell, and if you notice new symptoms as you do more, talk to a doctor.

How hard should exercise feel when I'm starting?

Moderate for most sessions: you can talk but not sing, about 5 or 6 on a scale of 0 to 10 (CDC, 2025). Start low and go slow, and finish feeling you could do a little more.

What is the talk test?

A quick way to judge effort without a gadget. If you can talk but not sing, you're at a moderate pace. If you can only say a few words without pausing for breath, you're working vigorously (NHS, 2024).

When should I stop?

Stop if anything hurts or you feel unwell. Before you start or step up, check with a doctor first if you get chest pain, pressure, fainting, a racing or skipping heart, dizziness or unusual breathlessness when you're active, or if any other item in step 6 applies. If you notice new symptoms as you do more, talk to a doctor.

Sources

This article draws on Jeremy Ethier's video on muscle soreness, Prof I-Min Lee's interview on Viva Longevity, Prof Marie Murphy's interview on BBC Radio 4's Just One Thing, and the studies and guidance listed below.

• Jeremy Ethier, Does muscle soreness mean muscle growth? (YouTube explainer, Built With Science, 2018)
• Exercise myths debunked, with Prof I-Min Lee (video interview, Viva Longevity, 2025)
• Exercise Special, with Prof Marie Murphy (radio and podcast episode, Just One Thing, BBC Radio 4, 2023)
• Langan-Evans, Clark & Erskine, Here's why you don't need to feel sore after a workout to know it's worked (researchers' article, The Conversation, 2022)
• NHS, Physical activity guidelines for adults aged 19 to 64 (health information page, 2024)
• CDC, How to measure physical activity intensity (health information page, 2025)
• UK Chief Medical Officers, Physical activity guidelines (government guideline, 2019)
• Stevens et al, Affective determinants of physical activity (narrative review, 2020)
• Williams et al, Acute affective response to a moderate-intensity exercise stimulus predicts physical activity participation 6 and 12 months later (prospective study, 37 inactive adults, 2008)
• US HHS, Physical Activity Guidelines for Americans, 2nd edition (government guideline, 2018)
• British Heart Foundation, Staying active (health information page, 2025; named, not linked, because the page offers a helpline)