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Story at-a-glance

• Exercise stops your immune system from overreacting after a muscle injury, helping prevent short-term pain from becoming chronic
• Daily physical activity, even as simple as swimming or walking, switches off inflammatory signals that keep pain going
• Your brain’s pain control system is retrained through consistent movement, reducing sensitivity, and interrupting the chronic pain cycle
• Studies show that even low-intensity exercise improves function and quality of life for people with arthritis, back pain, fibromyalgia, and other chronic pain conditions
• Movement is one of the safest and most effective ways to calm pain, improve resilience, and restore your body’s natural ability to heal

Most people think of muscle pain as a short-term issue. You tweak something, it stings and within a couple of days, it fades. But when that recovery process stalls, the pain doesn’t just linger — it digs in, spreads, and begins to reshape how your body and brain experience discomfort.

This is the point where temporary soreness turns into chronic pain, where that dull, nagging ache becomes the new normal. It affects more than just your muscles. Your sleep suffers. Your energy drops. Over time, your brain circuits that process pain grow more sensitive, creating a vicious cycle that’s hard to break. What determines whether you bounce back or break down? That’s the question researchers at the State University of Campinas in Brazil set out to answer.1

And what they uncovered was a precise biological shift — a moment when your immune system flips from repair mode to persistent inflammation. That shift doesn’t happen randomly. It’s triggered by specific molecular switches and, most importantly, movement appears to control the outcome. To understand how that switch works, and what to do to control it, let’s look at what the researchers found.

How Exercise Shuts Off Inflammatory Pain Before It Starts

The 2025 study, published in PLoS One, uncovered a powerful immune response that determines whether muscle pain fades or turns chronic.2 Researchers found that certain immune cells release pain-triggering chemicals when they sense injury or stress in the body. If that response stays switched on too long, it keeps your tissues inflamed — and the pain doesn't go away.

• Blocking this immune reaction reduced both pain and inflammation — In the lab, scientists triggered mild muscle inflammation in mice and saw a sharp rise in a pain-related chemical. But when they gave the mice a compound that shut down the immune trigger, both the inflammation and the pain dropped significantly.

• Regular movement stopped the pain response from starting — Here's the striking part: when mice swam daily before the inflammation began, that damaging immune response never kicked in. These active mice had far lower levels of the pain-inducing chemical and recovered quickly, without developing chronic pain like the sedentary mice.

• Exercise activated the body’s natural pain relief system — The research showed that physical activity signals your immune system to calm down instead of staying in attack mode. In effect, exercise flipped the body from inflammation to recovery.

• When that signal was blocked, exercise stopped working — To confirm the role of this anti-inflammatory signal, researchers blocked it chemically. As a result, even the mice that exercised lost the pain-fighting benefits, suggesting this signal is essential for turning down inflammation after activity.

• This study helps explain why movement prevents long-term pain — The big takeaway? Regular physical activity sends calming signals to your immune system, preventing it from going into overdrive. That makes movement a powerful, drug-free way to stop pain from becoming a chronic condition.

Your Brain Trains Itself to Feel Less Pain — or More

A study from University of Iowa researchers, published in The Journal of Physiology, looked at how physical activity affects your brain’s ability to process pain. For most people, working out makes pain feel less intense, but for some, it actually makes pain worse. The outcome depends on how your nervous system responds to exercise.

• Your brainstem has a built-in pain dial that exercise turns up or down — The researchers focused on a part of the brainstem called the rostral ventromedial medulla (RVM). Think of it like your body’s pain control center. When you move your body, the RVM releases natural chemicals that quiet down pain signals traveling through your spine.

• When your body’s built-in painkillers kick in, pain fades naturally — This process is called exercise-induced hypoalgesia, or EIH. It’s what happens when physical activity turns on your brain’s pain-relief system. As endorphins flood your nervous system, you become less sensitive to pain, even if the source of that pain is still there.

• But for some people, certain types of exercise crank the pain dial up instead — The same study found that in some cases, exercise triggers a pain increase called exercise-induced hyperalgesia. This happens when a different brain chemical system gets overstimulated. Instead of calming pain, it amplifies it. Your personal pain threshold, workout intensity, and how your nervous system is wired all affect which direction the pain dial turns.

• Knowing your body’s reaction to exercise helps you pick the right type of movement for relief — The takeaway? Your brain isn’t fixed when it comes to pain; it learns and adapts. By understanding how your body reacts to different types of activity, you can train your brain’s pain circuits to work with you, not against you.

Exercise Delivers Meaningful Gains for People with Chronic Pain

In a paper published in the Cochrane Database of Systematic Reviews, researchers analyzed data from 381 studies, 264 of which compared physical activity to either no exercise or minimal intervention in adults with chronic pain.3 Conditions included osteoarthritis, rheumatoid arthritis, fibromyalgia, low back pain, period pain, and more. Each study tested forms of exercise such as strength training, flexibility work, balance routines, yoga, tai chi, or aerobic activity.

• Pain severity dropped modestly in most trials — While results weren’t always consistent across different types of exercise or follow-up periods, most reviews reported a small-to-moderate drop in pain intensity.

In seven reviews, the reduction was significant — more than a 10-point improvement on a 100-point scale. In three reviews, pain dropped by more than 30% from baseline, which is the minimum benchmark typically used in drug trials to define meaningful relief.

• Physical function improved more reliably than pain scores — In 14 of the reviews, people who exercised experienced statistically significant improvements in how well they could move and carry out daily activities. One review even reported large effect sizes. For most others, the gains were small to moderate, but consistent. This suggests that even when pain didn’t fully resolve, people were able to function better with it.

• Psychological and quality-of-life outcomes showed mixed results — For mental health and emotional well-being, exercise worked for some people but not for others. Some reviews showed large improvements in quality of life after strength training, while others showed little or no difference. Importantly, no psychological harm or worsening of symptoms was reported in any group.

• Adverse effects were minimal and rarely serious — Only 25% of studies actively monitored for side effects, but among those that did, the most common complaint was temporary muscle soreness. This discomfort usually resolved within a few weeks. One review that tracked mortality found a non-significant trend toward lower risk of death in the exercise group.

• Intensity, type, and frequency of exercise varied widely — Some people worked out once a week, others several times a day. Sessions ranged from two minutes to two hours. Interventions included water aerobics, resistance training, tai chi, yoga, and core stability work.

This variety made it harder to draw precise comparisons, but also shows that there’s a lot of flexibility in finding an approach that fits your preferences and limitations. Overall, the takeaway was still clear: physical activity is unlikely to harm and often helps ease chronic pain, improve mobility and enhance quality of life.

Move Often, Recover Faster — How to Break the Pain-Stiffness Cycle

If you’ve been dealing with chronic pain for a while, you know how tempting it is to stay still. But avoiding movement makes your muscles weaker, your joints stiffer, and your pain more persistent. Staying active, even just a little at a time, helps lower pain, restore function, and protect your quality of life over time.

You don’t need to push through grueling workouts or pretend you feel fine. You just need the right type of movement, done regularly, in a way that your body handles. Here’s what I recommend to start rewiring your pain pathways and regaining mobility without making things worse:

1. Start with low-impact movement to interrupt the inflammation loop — Gentle activities like walking, tai chi or stretching help your body send the right immune signals — the same ones researchers have found switch off the inflammatory response that keeps pain going.4 Even minimal-intensity movement improves circulation, reduces stiffness and keeps your tissues from getting stuck in the pain cycle.

2. Use strength training to rebuild support around painful joints — Weak muscles leave your joints unprotected and prone to damage. Light resistance exercises, such as bodyweight squats, resistance bands, or hand weights, stabilize your spine, hips, and knees. This type of movement is especially useful if you’re dealing with back pain, arthritis, or fibromyalgia.

3. Be consistent to retrain your brain’s pain filter — Your nervous system adapts to what you do often. Short, daily movement sessions help rewire the pain-processing areas in your brain and make them less sensitive over time.5 Pair your routine with a habit you already have, like brushing your teeth or making coffee, so you’re more likely to follow through.

4. Track your pain levels and adjust gradually — Don’t expect to feel great every time you move, but do pay attention. Rate your pain on a 0 to 10 scale before and after each session. If it spikes higher than usual, scale back or try something easier the next day. Over time, you’ll build tolerance without triggering flare-ups.

5. Add variety to activate more parts of your brain and body — Mixing things up helps both your muscles and your mind. Alternate walking with yoga, swimming with resistance training or balance work with light stretching. Novelty doesn’t just keep things interesting — it keeps your brain engaged, your nervous system flexible and your pain response in check.

You don’t have to be perfect, just persistent. The right kind of movement at the right dose helps restore balance in your immune system, calm your pain circuits and give your body the chance to recover.

FAQs About Exercise and Chronic Pain

Q: What causes muscle pain to become chronic instead of fading?

A: When your body doesn’t resolve inflammation after a minor injury, your immune system stays switched on too long. This prolongs pain, spreads inflammation, and sensitizes your brain’s pain circuits, turning temporary soreness into long-term discomfort. Movement plays a key role in preventing that shift by calming the immune response.

Q: How does exercise stop pain from becoming a chronic problem?

A: Regular movement turns off the immune signals that keep inflammation and pain going. In lab experiments, active mice didn’t develop chronic pain after injury, while sedentary ones did. Exercise triggered natural anti-inflammatory pathways that helped the body recover faster and with less pain.6

Q: Why do some people feel better after exercise, while others feel worse?

A: Your brain has a built-in pain control center that adjusts how strongly you feel pain. For many people, exercise activates natural painkillers like endorphins, reducing discomfort. But in some cases, the wrong type or intensity of exercise amplifies pain instead. Understanding your personal pain threshold helps guide what works best.7

Q: Is exercise safe for people with arthritis, fibromyalgia, or other chronic pain conditions?

A: Yes. According to a large Cochrane review of 381 studies, most people with chronic pain benefited from regular physical activity. Pain intensity often dropped, function improved and side effects were rare and mild — typically short-term muscle soreness.8

Q: What kind of movement should I start with if I have chronic pain?

A: Begin with low-impact activities like walking, tai chi, or gentle water exercises. Focus on consistency over intensity. Add light strength training to support joints, track how your body responds and mix up your routine to stay engaged. This helps rewire your brain’s pain circuits and keeps inflammation in check.

Sources and References

• 1, 2, 4, 6 PLoS One February 11, 2025
• 3, 8 Cochrane Database Syst Rev. 2017 Apr 24;2017(4):CD011279, Discussion
• 5, 7 J Physiol. 2017 May 26;595(13):4141-4150