Nutrition, Adventure, and the Woman
By Larry Bartlett
Two dusty-faced hunters walk into a bar. The man looked bewildered and thin like an explorer; the woman, broad shouldered and stout legged like a hockey player. They ask for a meal and a beer. The bartender says, “Hold up! You’re gonna need to step on this here scale before placing your order, ‘cause men and women don’t eat the same amounts and we’re in short supply of grub ‘round here—can’t be wasteful!” They complied, and the bartender says, “What’s goin’ on here, my scales must be jacked up. Y’all weigh the same; that can’t be right.”
The nature of males and females working together cohesively to survive coalesced with relatively similar requirements for energy and macronutrient intake. In fact, a recent review published in the Journal of the International Society of Sports Nutrition (JISSN) suggests that while recommendations for vitamin intake may vary slightly between sexes, consumption of energy and macronutrients can be estimated similarly depending on energy expenditure and body weight. Coker’s research group has demonstrated a tremendous physiological resilience in women during the Alaska Mountain Wilderness Ski Classic (an unsupported, ultra-endurance, winter skiing event across the Brooks Range). Moreover, the women in this particular event carried more weight/body weight and still finished alongside the men.
My work with the Coker lab at the University of Alaska Fairbanks detailed the physiological benefits of backcountry hunting in the Spring 2019 Hunt Alaska issue. While we did not have any female participants in that first study, our overall initiative devoted to the health benefits of backcountry hunting was just getting started. In the fall of 2018, we recruited four women hunters between the ages of 33 and 69. We are still analyzing and interpreting the data that will include a thorough description of their macronutrient intake, energy expenditure, and other parameters such as body composition, blood work, and molecular imaging of muscle and liver.
From what we have learned so far, it seems relatively clear that women can follow recommendations for dietary intake based on their activity levels and body weight. The review previously mentioned in JISSN suggests that individuals estimate their caloric consumption based on body weight and the duration/intensity of the activity. For example, one might start with daily consumption of 25 kcal/kg/body weight for participation in a moderate exercise program of 30 min/day for around 3 days a week. As the intensity and duration of physical activity increases to numerous hours of activity on almost every day of the week (like on a backcountry hunt), the recommendations would increase up to 70 kcal/kg/body weight. All of these calculations assume the need to maintain caloric balance with convenient access to food calories; which we have learned may not be practical or even feasible depending on the extremes of the backcountry experience. Based on our own data collected under unscripted backcountry settings, and not in a controlled fitness center, it seems that we recover and maintain our skeletal muscle even with a 50% caloric deficit. In all fairness, that estimation is based on the initial studies being conducted in middle-aged males. Our 2018 study included female participants. We are now analyzing data in hope of providing gender-specific information to corroborate our earlier work. Stay tuned!
Regarding macronutrients, there is a lot of information out there on any number of fad diets ranging from Keto to Gluten Free to South Beach. Whether you consider yourself an “athlete” or just want to get serious, it would be wise to cast unsustainable fad diets aside and simply think about what your body needs for activity. Similarly, if you think you are gluten or lactose intolerant, then get checked for it. So what, then? According to the standards for athletes suggested by the JISSN, an average individual should go by these numbers for macronutrient intake: 20% protein (1.0 g/kg/body weight), 20-35% fat (0.5-1.5 g/kg/ body weight) and 45-60% carbohydrate (3-5 g/kg/ body weight). Please use these percentages as a guide, as we are quite capable of adequate recovery assuming sufficient sleep and multiple, albeit limited feedings throughout the day.
Depending on intensity and duration of an activity, the absolute amounts or g/kg/body weight may change, but the proportions should remain relatively constant. One possible exception would be an increased need for protein with sustained, high levels of intense physical activity. Research has shown that protein needs may approach 2.0 g/kg/body weight and should come predominantly from high-quality and complete (containing all the essential amino acids) proteins like meat, poultry, fish, eggs, and dairy. Beyond the general percent recommendations for fat intake, a good rule of thumb is to increase your intake of polyunsaturated omega-3 fatty acids like eicosapentaenoic acid (EPA), docohexanoic acid (DHA), and alpha-linolenic acid (ALA). Don’t worry! Getting these healthy fats is easy. Simply consume more salmon, mackerel, herring, grass-fed beef, or wild game for EPA and DHA, and increase intake of walnuts and flaxseeds to get ALA. Increased consumption of these types of fats are good for your heart and may reduce inflammation and even promote better recovery.
The last pointer is relevant to carbohydrate intake. Most of your carbohydrate intake should be in the form of whole grains, wild rice, etc. as it absorbs more slowly. Small amounts of simple sugars are also very effective in replenishing glycogen (stored as glucose) in liver and skeletal muscle immediately after a long and intense bout of activity.
The backcountry can be stressful enough as it is. Don’t wait until yourtrip to try any new foods. Experiment with your tolerance at home, pre-hunt, by incorporating them with your physical training regimen. This is especially important if you are spending major dollars for a once-in-a-lifetime trip. While not typically catastrophic, diarrhea, stomach cramps, and/or nausea will sour the adventure. If your typical diet is very low in fat, and you are planning to increase fat intake to save pack weight, you might want to ramp up your pre-hunt intake of fat a bit to build up the necessary enzymes to digest it. If you don’t use it, you lose it, and your gut’s capacity to digest foods is no exception.
So how does this look in a typical meal plan for an active, 135-pound female? For help with this strategy I recruited the experience of my friend and collaborator, Sheri Coker. She’s a 61-year-old huntress who’s fit and food smart. She co-authored this article and is intimately involved in our collaborative health studies, plus she’s the ultimate hunter-foodie. She put together a relatively simple strategy that will not break the bank. Many of the items you can put together yourself. Homemade trail mix made with nuts will increase your intake of polyunsaturated fats and improve your kcal/weight ratio. Trail mix formulas can be adjusted to your liking and modified for an “eat-on-the-run” strategy. This will stretch out your dietary intake, as you may not feel like eating a huge meal in the evening.
We are typically exhausted by dinner time. However, if you are feeling exceptionally hungry at dinner, we love adding dried potato mixes to freeze-dried meals, remembering to increase the amount of hot water. This is an easy and tasty way to increase carbohydrate intake.
While we are not endorsing particular products, the following meal plan meets the general guidelines discussed thus far and can be increased or decreased relative to body weight and/or the physical and mental stresses of the adventure. This plan dials in at 20% protein, 30% fat, and 50% carbohydrates, for a total of around 1,600 kcal/day. You will be operating in a negative caloric balance with any significant amount of activity. Fortunately, almost everyone has plenty of fat stored to serve as an endogenous fuel source to make up differences without any real impact on performance. This plan will save you 25-50% on the weight of your food kit. This meal plan also assumes some downtime due to weather, during which you will be resting, recovering, and minimizing your caloric requirements. Almost no one goes full throttle every day, all the time. It just does not work that way in the backcountry. Embrace the down time and you will be fit to fight without carrying a grocery store on your back or in your raft. You will be glad you did.
Larry Bartlett is the owner of Pristine Ventures based in Fairbanks, Alaska, and is an avid, hardcore outdoorsman. Pristine Ventures offers a slew of resources for backcountry hunters and fishermen like selling top-quality packrafts and canoes that can hold loads needed for outdoor activities. Larry also helps plan hunts for DIY hunters and provides equipment rentals.