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Nutrition tips for training in the heat


Triathletes and endurance athletes are very susceptible to dehydration and even more so, a heat-related injury at this time of the year.  Whereas in the cold/cooler months of the year, athletes can get away with haphazard fueling and hydration strategies, now is the time in the year when a poorly planned (or early-season) fueling/hydration regime will negatively affect training sessions, racing potential and health.  

Let it be known that training in the heat is incredibly stressful for the body. Seeing that training (in any environment) already creates difficulty for the body to adequately digest and absorb nutrients and fluids, you can imagine why so many athletes experience harmful health issues, GI struggles, extreme fatigue and so many more issues during the summer months when training for an event.
If you think about those who succeed well in endurance events, every athlete is getting tired from glycogen depletion and dehydration and central nervous system fatigue but those who can minimize these performance-limiting issues the longest (ex. proper pacing, great fitness, excellent nutrition/fueling/hydration), is the one who slows down the least and keeps the body functioning in good health and thus, the one who is the most successful on race day. It's also important to note that each athlete will have his/her own threshold for when the body begins to experience a decline in health and performance from dehydration and glycogen depletion - particularly in the heat. 
To keep your body functioning well (in training and on a daily basis), it's extremely important that you do your part and not let your fueling/hydration regime become a game of guessing - especially during the times when you feel your health/performance suffering during training.
Why athletes struggle to stay in good health and perform well in the summer months:

-Not staying well-hydrated on a daily basis (before/after workouts and during the day)
-Not bringing along fluids/nutrition when running (especially off the bike)
-Not comfortable drinking while running/riding 
-Rationing fluids to avoid stopping (or not enough places to refill bottles)
-Not enough hydration bottle cages on the bike (or if they are on, not easily accessible)
-Not using sport nutrition products properly (not enough or too much carbohydrates, fluids and electrolytes)
-Afraid to use sport nutrition products or not planning ahead and relying only on water (or nothing at all)
-It's only a "short" workout - you feel you don't need it

I could go on and on and on. 

There are dozens of excuses and reasons that athletes have as to why fluid/electrolyte/calorie needs are not being met during training and racing and not only is it holding you back from training consistently and executing well during workouts, it is also extremely damaging to the body - placing you at risk for injury, sickness, burnout and other serious health complications. 

Common side-effects of dehydration: 
  • headache
  • dizziness
  • blurred vision
  • loss of focus
  • chills
  • no appetite post workout
  • excessive sleepiness
  • extreme weakness
  • low blood pressure
  • stop sweating
  • dry mouth
  • dark urine
  • dry skin
  • no/little urination
  • extreme cramping
  • bloating/puffiness 
  • excessive thirst/lost of thirst
  • rapid, elevated pulse (despite effort slowing down)
  • muscle spasms (during and post workout)
Are you currently experiencing any of the above? If yes, your current fueling/hydration strategy is NOT working for you. 

Every human body is different but we must pay very close attention to our body signs/symptoms/signals when it comes to training and racing in endurance events. If you do not make the effort to keep yourself in good with proper fueling and hydration (and pacing), you will be forced to spend a lot of time getting your body healthy again before you start even thinking about training again. 

To help you out, here are a few very simple tips to ensure that you are staying hydrated during your workouts (and races): 

  • Be sure to have a sport drink with you for all workouts lasting more than one-hour - this should contain a mixture of electrolytes, carbohydrates and fluids in an appropriate concentration to digest well and to be efficiently absorbed. I suggest a hypo or isotonic solution with no more than 10-14g carbohydrates per 8 ounces but at least 120mg of sodium per 8 ounces in the heat to optimize gastric emptying.
  • For intense or very sweaty/hot workouts lasting less than an hour, you should still use a sport drink with at least 10g carbohydrates per 8 ounces and at least 120mg sodium per 8 ounces.
  • Aim for 24-32 ounces of fluid on the bike per hour and at least 10 ounce fluid per 10-15 minutes while running (this should be in a sport drink - not plain water in the heat!).
  • Aim to sip your bottle on the bike every 10-12 minutes (you need at least 3-4 gulps to ensure that you are getting in around 3-4 ounces of fluid) and 1-2 sips every 5-8 minutes while running. Frequent drinking on a schedule will not only help to delay fatigue and prevent dehydration but will prevent overdrinking on fluids (particularly ice cold water).
  • While keeping your insides hydrated is critical, consider ways to keep your body cool on the outside. Suggestions include exercising early morning or in the evening and avoiding workouts in the heat of the day (10-5pm). Choosing indoor workouts over outdoor. Using water/ice to cool yourself while exercising. Wear a cooling towel/cooling sleeves. Use a visor over a hat. Choose shady areas over direct sunlight. Wear sunscreen to prevent burning.
  • Always plan ahead with your bottle refill stops. Be sure to STOP before you really need to stop so you are never rationing your fluids or going without.
  • Be sure you are setting yourself up for good hydration behaviors. Cages/hydration systems on the bike should be accessible and easy to use in ALL conditions (ex. bumpy roads, rain, technical courses, etc.). Your run courses in training should allow you to refill bottles that you bring with you OR set up bottles on your course. Everything you do in training should be practice for race day.
  • Wear a hydration belt/pack so you can drink what you drink, when you want to drink it. There are many types on the market - find one that works for you and never run outside without it.
  • Do not wait for thirst to kick in during endurance workouts/racing to start drinking. Start drinking/fueling early. An athlete who waits to drink until he/she is thirsty is already behind on fluid requirements and many times, this will cause an athlete to drink an excessive amount of water (as it may be more palatable as a race/training continues) and may cause hyponatremia (very serious) or may cause a sloshy stomach/bloating/stomach cramping by trying to drink too much at once (often a hypertonic/concentrated amount from guzzling a lot of drinks at aid stations or stops at gas stations in training).
  • Make your fueling/hydration strategy during workouts as simple as possible. You should not be using several different methods of consuming electrolytes, calories/carbohydrates/sugars and fluids. Also, DO NOT overconcentrate your flasks/bottles.
  • Pace yourself and be OK with slower paces but a higher RPE. Even mild dehydration can negatively affect performance and can cause drowsiness, irritability, loss of concentration and headaches - none of which are performance enhancing or healthy. When dehydration worsen, serious issues occur which affect the heart, brain, muscles and organs (ex. kidneys). Successful athletes know how to pace an effort so that nutrition/hydration is helping to fuel and hydrate the effort. If you overwork your body, it is not possible to overfuel/hydrate the body to meet your training/racing demands. 

And lastly, you have to be respectful of your body in the heat. If you are feeling any changes with your body that concern you, first slow down and don't be afraid to stop. Remind yourself that when your body starts to shut down or gives you signals/signs that something is wrong (ex. headache, chills, vision changes, etc.), your body is no longer trying t adapt to training stress but it's trying to protect you. Never get upset at your body for a bad workout or race if it is simply trying to protect you from a serious heat or other-related injury. 

 There are far too many athletes failing with workouts and experiencing negative health issues from poor fueling/hydration strategies before/during/after training and improper pacing. Sport nutrition is a complicated area with many misguided tips and suggestions that are not always practical or healthy. If you know someone who can benefit from this blog, please share.