GOAL: To give rock climbers practical sport nutrition for at the gym or at the crag.


E-mail your questions and comments to: onsitenutrition@gmail.com

Oct 30, 2008

Nutrition Research Survey!!!



As you may have noticed, there is very little scientifically based nutrition information out there targeted specifically at rock climbers. I am trying to change that, and hope you will help!

In order to figure out what future research needs to be done in nutrition in rock climbers, and to determine what nutrition information rock climbers need, I am doing a survey research study!

My research study is formally entitled “Food motives and typical food choices while living at home versus during outdoor rock climbing trips”. Oof! Quite the mouthful! Basically, with this study I am hoping to find out what foods and drink rock climbers choose, why they choose those foods and drink, and how this might change when climbers go on outdoor rock climbing and camping trips. The information gathered from this study will help decide future research. It will also help figure out what nutrition issues climbers may have, what nutrition information they need and how to best give them this information.

This study is an online survey. You may participate if you are between the ages of 18 and 55 and have been on at least one rock climbing and camping trip of at least 5 days duration within the past year. The survey is open to all Canadian and US residents. Your answers will be kept confidential and at no point will you be asked to give identifying information, ie. you will never need to give your name, address, phone number, e-mail, etc. Also, an ethics committee at the University of Manitoba approved the study.

You have until January 23rd 2009 to complete the survey.

TO TAKE THE SURVEY click here.

If you have any questions or concerns, feel free to contact me or my supervisor:
Krystal Merrells: KJMnutrition@gmail.com
Dr. Miyoung Suh:

You can also visit Dr. Suh's University of Manitoba webpage by clicking here. Or, visit the study's webpage by clicking here.

STAY TUNED to this blog! By May 2009, I hope to have all of the data put together and summarized on this blog so that you can see the results of the study.

Thank you for your participation!

Krystal Merrells

Oct 10, 2008

Are you drinking enough?

Hydrating for high performance

When I was in Squamish this August, the group of people I was with and myself noticed that we simply weren’t drinking enough…and I’m not talking about getting enough pints in at the Brew Pub . I’m talking about hydration! (not inebriation…)

In August, we’d be out in the forest and get on problem after problem…it would be half way through the day and we’d notice that our water bottles hadn’t emptied at all. Not only were we thirsty, but we were also sluggish.

When talking to other climbers out there, it seemed many people noticed that even back home at their local gym, they simply weren’t getting enough fluids.

Poor hydration and poor performance are practically synonymous. So, this blog post is about the importance of hydration, and how to drink enough!

What does fluid do for me?

Your body needs water to…

  • Maintain blood volume, which allows nutrients and oxygen to get to the rest of your body

  • Help digest food as part of saliva and digestive juices that break down and absorb food

  • Provide an environment for all biochemical reactions of the cell to occur

  • Lubricate joints and cushion organs and tissues

  • Eliminate waste from the body (#1 and #2)

  • Regulate core body temperature at 37ºC via sweat

That last point can be very important for athletes who are training in hot and humid conditions. When we exercise, our muscles produce heat as a sort of “by-product” of the work they are doing. The heat can build up and be stored in the body, which may cause the body’s overall temperature to rise. We sweat to keep our body temperature at a steady 37ºC.

What are the consequences of dehydration?

Unfortunately, we cannot adapt to chronic dehydration. A loss of only 1-2% of our body water is enough to significantly decrease athletic performance. This amount of fluid loss is common in a one-hour training session, where sweat losses can be ½ to 1½ litres!

Symptoms of dehydration include fatigue, light-headedness, headaches, muscle cramps and low endurance. When dehydrated, exercise may seem harder then usual.

Because body fluids are essential for proper functioning of joints and related tissues, dehydration also increases risk of injury. This is especially important for us climbers who put so much stress on joints and tendons!

When dehydrated, on the inside of the body…

  • Blood volume and blood pressure drops, resulting in less oxygen being transported to the muscles

  • Less blood gets to the skin, so less sweat is produced - the body becomes less able to get rid of the build up heat

  • Heart rate speeds up

  • Consumed fluids and foods are released from the stomach more slowly - the body doesn’t absorb nutrients or water as effectively.

Dehydration in extreme cases: heat illnesses

When proper fluid intake is avoided for too long in hot or humid conditions, athlete’s can develop heat illnesses. In the first stage, the illness is simply annoying and can greatly affect performance. In the last stage, body temperature rises so high that it can cause coma or death! Here are the heat illnesses and their signs and symptoms:

  1. Heat cramps: These are painful, involuntary and intermittent muscle spasms that can occur in any muscle group.

  2. Heat exhaustion: This is more hazardous as the sufferer’s mental status is changed; they become irritable, dizzy and have poor judgment. Other symptoms are nausea, headache, sudden fatigue and profuse sweating. Skin colour may be pale. When not treated, this can develop into heat stroke.

  3. Heat stroke: This occurs when body temperature rises to 41ºC and above. This illness is very dangerous and could lead to coma or death. Central nervous system dysfunction causes loss of motor coordination, confusion, delirium and loss of consciousness. At a body temperature of 42ºC and higher, protein within the body coagulates and causes cell death – the body cooks itself! This leads to multi-system organ failure. Symptoms may include reddened skin, rapid heartbeat, quick shallow breathing, normal-profuse sweating, personality changes and fainting.

How do I know if I’m well hydrated?

Check your urine. That’s right…you don’t have to share it with the world, but the next time you go #1, check the volume and colour. If you pee only a small volume and your urine is dark, then you’re dehydrated!

Don’t count on your thirst. If you’re thirsty, then you’ve already lost 2% of your total body fluids, which mentioned earlier, is enough to hurt your climbing! If you’re thirsty, you’re already dehydrated.

How much should I drink and when?

Before exercise: Start off well hydrated by drinking 2-2½ cups of fluid 2 hours before, and try ½ to 1 cup 10-20 minutes before climbing or a competition.

During exercise: Try to match fluid input with fluid output. To find out your sweat rates, weigh yourself before and after exercise in the nude or, (for the more discrete) in the same clothes before and after. The amount of weight lost during exercise is the amount of body fluid lost: 2.2lbs (1kg) equals 4 cups (1 litre) of fluid that needs to be replaced. You can also try drinking ½ to 1 cup of fluid every 20 minutes during your session.

After exercise: Aim for complete re-hydration. Try drinking 3 cups of fluid for every pound of body weight lost within 2 hours after exercise.

What do I drink?

Before climbing and in the first hour, water is a good choice. But after one hour goes by, you want to switch to a sports drink, such as Gatorade or Powerade.

What about sports drinks?

Sports drinks have carbohydrates and electrolytes to help replenish what you lost in that first hour of climbing. Plus, they are concentrated 4-6%; at this concentration they cause little tummy upset and allow maximum water absorption into your body. However, some people still find these drinks too concentrated. If these give you tummy discomfort, just dilute with water until you find the right concentration – you’ll still get the benefit of some carbohydrate and electrolytes.

You can also make your own sport drink!

  • 1 cup of your favourite fruit juice

  • 1 cup of water

  • 1 pinch of salt

  • Mix and enjoy!

Sport drinks and juices also make good recovery drinks after your training session. The simple fast absorbing carbohydrates in these drinks stimulate muscle recovery. Milk post-exercise is also great for recovery because it has carbohydrate and high quality protein.

What about energy drinks?

Energy drinks, like Redbull or Rockstar, are less ideal for good hydration. Carbohydrate concentration in these drinks ranges from 20-25%. Research studies have shown that drinks with a carbohydrate concentration of 8% and higher actually slow down fluid absorption into the body.

What about alcohol?

Alcohol and sports seem to go together. Remember that alcohol has a diuretic effect – that is, “once you break the seal”, it causes you to pee more, causing you to lose more fluids. During or after a hard day of climbing, alcohol won’t help you re-hydrate or recover.

To sum it all up

  • Dehydration is one of the most common causes of poor performance, and is one of the easiest things to fix in the diet!

  • Be aware of the symptoms of dehydration: fatigue, light-headedness, muscle cramps, struggling with exercise

  • Take action when you start to notice signs of heat illness in yourself or your belay partner or spotter: nausea, dizziness, sudden fatigue, profuse sweating, confusion, irritability, rapid shallow breathing. Drink some cold fluid and get into the shade!

  • Drink fluids before during and after training sessions to prevent dehydration and to optimize recovery

  • Choose water, juices and sports drinks over energy drinks and alcohol

Hydration table:

Before exercise


2 hrs before

10-20 minutes before

How much?

2 cups

½ - 1 cup


Water or

Gatorade G2

First hour of exercise

Every 20 minutes

½ - 1 cup


For exercise lasting longer then 1 hr

Every 20 minutes

½ - 1 cup

Sport drink (bought or homemade)

After exercise

Within 2 hours after

3 – 6 cups

Water, sport drink, milk

Practical Tip:

You know you need to drink 1/2 - 1 cup of fluid every 20 minutes during training...but are you really going to bring a measuring cup with you to the gym or to the crag??
  • If your water bottle doesn't have volume measurements on it, measure out 1/2 or 1 cup of fluid at home and pour into your water bottle to see how much it fills
  • Mark lines on your water bottle for every 1/2 or 1 cup of fluid - use a Sharpe, nail polish, or stickers!
  • You can either set a timer or force yourself after each 2-3 burns to take a swig of fluid - make sure your swig empties your bottle to the next marked line!

Onsite Nutrition now has its own facebook group. Join to be updated on new blog posts, ask questions, or start discussions.

Any questions?

References and Readings

Clark, N. (2003). Nancy Clark's Sports nutrition guidebook, 3 Ed., Human Kinetics.

Covertino, V.A., Armstrong, L.E., Coyle, E.F., Mack, G.W., Sawka, M.N., & Sherman, W.M. (1996). American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc, 28(1), i-vii.

Gibson, J. (2006). Energy drinks. SportMedBC factsheet at www.sportmedbc.com.

Murray, R. (1996). Dehydration, hyperthermia, and athletes: Science and practice. Journal of Athletic Training, 31(3), 248-252.

Parsons, D. (2005). Fluid first - hydration in sports. SportMedBC factsheet at www.sportmedbc.com.

Weinmann, M. (2003). Hot on the inside. Emerg Med Serv, 32(7), 34.