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Cramping + Dehydration

The day is going well, you’ve had a killer swim and your bike speed was much faster than expected. You start the run and BAM… all of a sudden it’s like your body is shutting down. Legs get heavy, nausea kicks in, your mouth is dry, there’s dizziness, and eventually muscle cramping along with the inability to ‘cool down’. Basically, your body has said ENOUGH! There are several reasons why your muscles cramp and it’s not always “just” dehydration. Jeff had a rough day out there on the run, and in my professional opinion, his nutrition was a bit off for the conditions of the day and he intervened with electrolytes a bit too late. The abdominal cramping Jeff experienced is primarily a result of poor nutrition and dehydration (versus leg cramping which is the result of inadequate training for race conditions).

Below I’m going to talk a bit about muscle cramping, explain the basics of dehydration and teach you the best way to prevent issues like this by creating a plan… and a backup plan!

Why Do We Get Muscle Cramps

The main risk factors for muscle cramps include; (genetics) a family history of cramping, previous occurrence of cramps during or after exercise, increased exercise intensity and duration, and inadequate conditioning for the activity. This explains the classic example of cramping on race day. During a race you’re typically working at a higher intensity than normal, and often over a longer duration than during training.

From a nutrition perspective, glycogen depletion (insufficient carbohydrate) or low energy availability can also contribute to fatigue and therefore cramping. This highlights the importance of getting your nutrition and fueling plans for long sessions and races spot on. I work with athletes three or more months in advance dialing in the appropriate race day fueling-hydration plan and recommend you give this as much attention as you do your swimbikerun training.

How is Dehydration A Factor in Cramping

When it’s hot or more appropriately when we get really hot, whether it’s through intense exercise or from baking under a garish sun, we sweat to cool our bodies. Without that sweat and the evaporative cooling that comes with it we can overheat and literally start cooking ourselves from the inside out, which isn’t exactly good for either performance or one’s health. Unfortunately, as we sweat we also dehydrate, losing precious water and salt, both of which are critical for normal bodily functions. It’s a bit of a catch 22. Either overheat or dehydrate or both – all of which are bad.

As a result of sweating out ‘water’, the watery part of your blood also drops, and the blood becomes more viscous, which leads to a higher heart rate, increased core temperature, and lower power production—i.e. reduced performance. There’s also a competition within your body for blood: Blood goes to the muscles for metabolic function; blood goes to the skin to get rid of the heat produced by the working muscles. As body water drops, this competition increases, and the blood flow to the skin takes precedence, primarily because heat is a greater threat to the body than keeping the muscles working. The fatigue you experience is a result of the drop-in blood flow to the muscles.

What Your Body Needs to Stay Hydrated

So now that we’ve established that hydration is the key to performance, let’s have a look at what else your body needs – besides water of course – to stay hydrated. Your small intestines are where 95% of nutrient and water absorption takes place. Physiologically, there are specific things the body needs to create a net water gradient in the small intestines so that it can absorb water.



Sodium (and no the answer isn’t just popping salt pills)

And on a smaller scale: potassium, magnesium, chloride, and calcium.

How To Create a Race Day Nutrition/Hydration plan… & Backup Plan

1.Assess your sweat loss (either at a lab or with an at-home test) and assess your caloric needs.

2.Select the products that work best for you - that may or may not be what’s offered on course and/or be what you “think” the pro’s are using. You may also use different things for the bike than you do on the run. SOS Hydration is my go-to mix and I like a combination of bars, nut butter and Skratch Chews (run only).

3.Test, adjust, retest, adjust, test again… see a pattern here? What works one day might not work on another. What worked last season may not be ideal this season. What you use on a cool day is vastly different than what you need on a hot and humid day. Prepare for your actual race day conditions- temperature, course and duration.

4.Write out a plan and a back-up plan. Sometimes the day goes exactly as you expect, but most of the time you’ll need to adjust as the race progresses. If you’ve fallen behind on calories or dropped a bottle of hydration have extra supplies to get back on track. In Jeff’s case, slowing his pace, consuming some fast-acting liquid calories and using a powdered electrolyte mix (not salt pills) would have helped alleviate some, not all, of the abdominal issues he experienced.

5.Get help- if you just can’t seem to get it right reach out to myself or another QUALIFIED sports performance nutritionist for help.

Elizabeth Inpyn is a sports nutritionist, former NCAA collegiate swimmer, and triathlete. She's currently working with endurance athletes, triathlon clubs, coaches and pros to dial in nutrition plans. Visit her website at Inpyn Coaching.

#cramping #dehydration #nutrition #plan #nutrients

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