True adventure is about defining your own path and breaking beyond your traditional rings of comfort to establish new performance potentials for your body that your mind may have once doubted. Whether you are planning 50 miles of single-track action on your mountain bike, some backcountry skiing, a long rock climbing ascent or a trek up to the summit of a 15,000-foot peak, the boundaries set by your mind can continue to be defied with the aid of proper nutritional planning for the long haul.

Extreme Nutrition Tip #1:
Fuel Frequently to Prevent ‘Engine Failure’

Unlike during rest when our glycogen (storage form of carbohydrate) reserves are maintained for a good 3-4 hours, during physical activity these stores deplete every 1-2 hours. If nutrition is neglected during an all-day adventure, this depletion can result in a mental ‘bonk’ with your body facing a muscle-wrenching wall. In other words, your body’s engine fails. To ensure optimal energy levels for sustained endurance, an adequate amount of fuel — plus some emergency fuel — should be included in your adventure pack before heading out.

Because all-day adventures are more aerobic in nature than shorter workouts, there is sufficient oxygen available for digestion of more diverse macronutrients (carbohydrate, fat, protein) during such efforts, although carbohydrate should still be the focus. While calories burned will vary based on the terrain, weather conditions (shivering increases calorie expenditure) and specific activity, adventurers should expect to burn about 3-4 calories per pound of body weight each hour of activity of which 30-50 percent should be replaced. For example, a 150-pound adventurer will burn about 450-600 calories each hour of which 135-300 calories should be replaced hourly.

Obviously, ease of travel will contribute to the foods chosen for all-day adventures, but common choices include non-perishable items such as freeze-dried foods, trail mixes, nut butter sandwiches, sports drinks, energy bars, dried soups and beef/turkey jerky.

Extreme Nutrition Tip #2:
Ensure ‘Nutrition’ Survival With Fluids

While your body can survive with insufficient fuel (food) for several months, failure to drink fluids can drive your body’s core temperature to a degree where your kidneys could fail and you could go into convulsions. If no fluids are taken in, it could even be fatal in a matter of hours.

Since sweat rates vary from person to person, it is important that each adventurer has an understanding of individual fluid needs before embarking on an all-day trip.

To determine your sweat rate and consequent fluid needs, weigh yourself (without clothes) before and after several lower intensity workouts. Every pound lost is equivalent to about 16 ounces of fluid that should be added to your current fluid routine to protect against dehydration during longer adventures. For example, if you train aerobically for an hour and lose two pounds, your sweat rate is 32 ounces per hour. Ultimately, the goal is for your post-workout weight to be within two percent of your pre-workout weight.

While on your adventure, hydration status can be monitored by peeing into a cup periodically throughout the day. Urine should maintain a pale yellow color as shades darker indicate dehydration and shades lighter indicate overhydration and an increased risk for another dangerous condition known as hyponatremia.

To help absorb fluids, include 100-250 milligrams of sodium for every eight ounces of fluid you consume. Remember, most of the foods we eat — including several items listed in extreme tip #1 — contain plenty of sodium and so electrolyte capsules are not generally needed.

Extreme Nutrition Tip #3:
Take Caffeine to Go Longer With Less Effort

Researchers from Georgia have recently discovered that caffeine dosing during prolonged exercise helps maintain blood glucose concentration. It was also shown to help reduce strength loss through its effects on the active musculature and nervous system that reduce fatigue and perceptions of effort, discomfort and pain. To yield these positive results, study participants were given a total of 2.4 grams of caffeine per pound of body weight split in dosages prior to and during their submaximal 2.25-hour effort.

For an all-day adventure, I recommend that you take smaller doses of 20-30 milligrams per hour. This amount can be effective in maintaining your alertness without becoming dehydrated. (A threshold dose of 300 milligrams can negatively affect hydration status).

Want more nutrition tips as you prepare for your next adventure? Kim Mueller, owner of Fuel Factor Nutrition (www.Fuel-Factor.com), is a registered dietitian and exercise physiologist who has helped fellow adventurers conquer multi-day adventure races, cross-country cycling trips, 24-hour mountain bike races and 100-mile ultra-endurance runs. Customized menu planning, nutrition coaching and health/sport enhancement programs are available to active individuals worldwide. She can be contacted at kim@Fuel-Factor.com.