Muscle Cramps: It’s Not Just Salt

The Rehab Runway Podcast

🎙️ Episode 7: Muscle Cramps: It’s Not Just Salt

Muscle cramps are one of the most frustrating experiences in endurance sport.

You’re 30 to 35 kilometres into a marathon. Your calf starts to flicker. Then it tightens. Then it locks. Race over.

For years, we’ve been told the same story: dehydration, low sodium, not enough electrolytes.

But what does the research actually say?

In this solo episode of The Rehab Runway, Luke unpacks the evidence behind exercise-associated muscle cramps (EAMC), including prospective cohort studies in Ironman triathletes and ultramarathon runners, laboratory cramp threshold trials, and emerging research on neuromuscular control.

If you’ve ever struggled with cramping in training or racing, this episode will help you rethink the cause and refocus your prevention strategy.

🧠 What You’ll Learn in This Episode

What exercise-associated muscle cramps actually are
Why the dehydration and electrolyte theory is incomplete
Risk factors identified in prospective endurance studies
The neuromuscular fatigue model explained simply
Who is more likely to cramp and why
Why stretching works immediately
The truth about pickle juice and TRP channel activators
Emerging evidence on cramp threshold training
The role of recovery, sleep, and cumulative fatigue
A practical framework to reduce your risk

🏃 Take-Home Messages

Muscle cramps are rarely random.

They are most consistently linked to:

Higher relative intensity
Previous history of cramping
Muscle fatigue and damage
Longer duration exposure
Conditions that accelerate fatigue

Hydration and electrolytes support performance, but they are not the primary cause of cramping.

The most effective immediate action remains gentle passive stretching.

The most effective prevention strategy is improving fatigue resistance through progressive training, strength work, pacing discipline, and adequate recovery.

Prepared tissues and prepared nervous systems cramp less.

🎧 Listen to the Episode

Available now on Spotify, Apple Podcasts, and all major podcast platforms.

If you found this episode useful, please consider sharing it with a runner or colleague, or leaving a review. It genuinely helps the podcast reach more people.

👉 Listen on Spotify

👉 Listen on iTunes

🎙️ About the Host

Hosted by Luke Nelson, Sports & Exercise Chiropractor, running coach, and strength coach.

📱 Follow Luke on Instagram: @sportschiroluke
🌐 Learn more & explore upcoming courses: www.healthhp.com.au

Blog: Muscle Cramps Suck: What you can do about them

References

Behringer, M., 2015. Are electrically induced muscle cramps able to increase the cramp threshold frequency. European Journal of Applied Physiology.
Behringer, M., 2018. Cramp training induces a long-lasting increase of the cramp threshold frequency. Scandinavian Journal of Medicine & Science in Sports.
Braulick, K., 2013. Significant and serious dehydration does not affect skeletal muscle cramp threshold frequency. Medicine & Science in Sports & Exercise.
Craighead, D., 2017. Ingestion of TRP channel agonists attenuates exercise-induced muscle cramps. Journal of the International Society of Sports Nutrition.
Miller, K., 2021. Evidence-based review of the pathophysiology, treatment, and prevention of exercise-associated muscle cramps. Journal of Athletic Training.
Schwellnus, M., 2011. Increased running speed and previous cramps rather than dehydration or serum sodium changes predict exercise-associated muscle cramping in Ironman triathletes. British Journal of Sports Medicine.
Schwellnus, M., 2011. Increased running speed and pre-race muscle damage as risk factors for exercise-associated muscle cramps in a 56 km ultramarathon. Clinical Journal of Sport Medicine