Hamstring cramps at night, cramps while sitting, or during training can send you into a writhing, screaming heap on the floor. And if it keeps happening, there’s something wrong. Here are some ideas that can save you some grief, and potentially a torn muscle.

To be honest, the exact cause of muscle cramping is largely unknown, with dehydration, fatigue, low potassium or sodium levels, low carbohydrate levels and very tight muscles all being sited. Although addressing these issues can help, it seems to be a combination of multiple factors rather than one significant one. But here’s what I’ve found.

My Thoughts On Hamstring Cramps

If you’re suffering from repeated hamstring cramps, first of all do your best to cancel out the effects of dehydration and low potassium, sodium and carb levels by sipping an isotonic drink throughout training. My weapon of choice is coconut water!

However, if you tend to cramp early in training, it’s likely to be caused primarily by how your body patterns the hip extension movement; over using the hamstring muscle group and under using the glutes. In fact, this ‘bad hip extension patterning’ can not only cause cramping early in a session, but also leads to cramping later on because the hamstrings are fatigued from working too hard. Fear not, it’s ‘fixable’, and I’ll explain my approach to this in just a moment. But first, how to alleviate your cramping hammies if they’re just kicking off!

What To Do When a Hamstring Cramps

1. Stretch out the muscle

To stop the pain, gently lengthen the muscle. Stretch it, extending your knee and flexing your hip (lift your straightened leg up, or reach for your toes). While cramping, the muscle shortens involuntarily into a knot. Contracting the muscle makes it worse, exaggerating the spasm (and the pain). Instead, gently stretch the muscle out encouraging it to let go. Don’t go too fast or hard, or you could tear the muscle.

2. Stop using it!

Stop doing anything that ‘fires it off’. The rest of the session needs to be changed. Once your hamstring cramps it will get worse, it won’t just go away.

I’ve seen fighters carry on training regardless (myself included), only to find the cramps became more intense with each attack, eventually leading to a muscle tear. Instead, back off and live to fight another day. Don’t fall for the false economy, costing you weeks of working around a tear, rather than just the remainder of the session.

3. Drink

Grab yourself an isotonic drink — topping up potassium/sodium, carbs and fluids. Either a commercial sports drink, coconut water or something like my fruit juice and water mix (more on that in the resources at the end).

So What’s Going On?

Cramping is most common in muscles that span two joints (like the hamstrings and the calves). These muscles can easily end up in a shortened state due to limb/joint position, and attempting to contract even further causes a spasm lock-down. Not fun.

How Can I Correct My Movement Habits?

If you overuse your hamstrings during hip extension moments (driving your knee back behind you), they’ll tire much quicker which can cause cramping. And if you’ve the habit of primarily firing the hamstrings when the hip is extended and the knee is flexed, the hammies are at an mechanical disadvantage, tying to contract when already in a shortened state. Watch out, spasm attack!

To fix this habit you must teach your backside muscles (glutes) to do the lion share of any hip extension movement. This will spare your hamstrings and boost your athletic performance too.

Before we activate your glutes, first we need to stretch the hip flexor muscles (to reduce any reciprocal inhibition on the glutes), and stretch the hamstrings a little too (to inhibit them and allow the glutes to do a larger share of the work).

1. Perform the step hip flexor and the lateral hamstring stretches.

2. Activate the glutes using the Cook Hip Lift.

If you find your hamstrings are cramping doing this exercise, shift the foot on the floor a little further from your backside and/or come onto the ball of the foot rather than the heel. Really focus on squeezing your backside to create the hip lifting action.

3. Further activate the glutes with side lying clams and x-band walks.

4. Use hip dominant exercises (such as deadlifts, stiff-legged deadlifts, and kettlebell swings) and mindfully ‘feel the glutes’ while performing them.

Closing Notes & Next Steps

When a hamstring cramp strikes…

  1. Stretch out the muscle
  2. Stop using it (if you’re exercising at the time)
  3. Drink an “isotonic” drink that contains potassium/sodium too.

To better prevent against hamstring cramps in the future, work on reducing how quickly they fatigue by…

  1. Improving glute muscle activation and movement patterning (sparing the hamstrings of so much work load)
  2. Strengthening the hamstrings (using hip dominant exercises such as deadlifts, stiff-legged deadlifts, and kettlebell swings) so they’re more resistant to fatigue – every effort becomes a smaller percentage of what they’re capable of
  3. Maintaining hamstring range of motion/flexibility, and mobility in the muscles around the hips

Focus on this for a month or two, and you’ll not only cure your hamstring cramps, but you’ll spare your lower back and knees, and add more strength, power and economy to all your lower body actions.

Invest in developing this, and you’ll drastically change how you move for the better.

Further Resources

To learn how to put together your own homemade isotonic drink, check out this section from my What Is My Ideal Fight Weight Class guide here.

If you want to sort out your nutrition, to make sure you’re getting all the nutrients needed to prevent bodily malfunctions, then have a look at my Fat Loss For Fighters guide here.

To further release the Hip Flexors (that serve as the parking brake against your hamstrings), take a look at my Release-Open-Anchor sequence to unlock the hips here.

To learn how to program your training to prevent muscle imbalances, future injuries, and ultimately move like an athlete, check out my guide – Strength and Conditioning for Muay Thai 101: A Science-Based Approach to Accelerated Athletic Development here.

I hope you find this article and the resources useful, and I wish you a robust, injury proof body!

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Don Heatrick

Founder of Heatrick Strength and Conditioning

Don Heatrick is a family man from the UK, former mechanical design engineer, European Muay Thai silver medallist, former pro Thai boxer (ranked 4th in UK while aged 40-years), a Muay Thai coach, podcast host, and the go-to expert on Muay Thai performance training with over 25 years of coaching experience.

Don helps ambitious fighters and coaches take their game to the next level by bridging the gap between Strength & Conditioning, Performance Science, and Muay Thai.

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