A Guide to Healthy Nutrition
Marty Smith
Introduction Most people embarking on a new or harder workout regime don’t consider their nutritional plan along with their workout plan. This is a big mistake, because if you don’t change your diet, your body may not be getting the most out of your workout efforts. If you do pay a little attention to your nutrition during a period leading up to your peak race (or during your effort to improve your body composition), not only will your muscles ―reap‖ the rewards of your efforts, but your athletic/overall health performance will also optimized. You will be leaner, more rested, less injury prone, and in overall better health. Bob Seebohar, a nutritionist for the U.S. Olympic Team, has termed this synchronizing of nutritional with a training season as ―Eating to Train‖ versus the often heard phrase ―I train to eat!‖ The human body needs macronutrients (water, carbohydrates, protein, and fat) and micronutrients (minerals and vitamins). This guide will help determine how much and what kind of each of these you should consume and how you should adjust this pattern as you go through your training ―season.‖ A Short Primer of Nutrition Let’s go over macronutrients first: Water—you should be drinking more water than the non-athlete. Your muscles need water to stay loose and ―lubricated,‖ and without water you will not be storing as much glycogen as you could be, which will mean a higher chance of running out of carbohydrates during a long race (anything over 3-4 hours). A simple guide to use is the color of your urine – it should be light in color with minimal odor. Other signs that you aren’t getting enough water are constipation, fatigue, and headaches. Any drinks with caffeine are diuretic, which means you will urinate more often, and you may actually lose water if these are all you drink (soft drinks, tea, coffee). If you lose more than 2 percent of body weight in a workout (which really isn’t that much, especially in hot weather), athletic performance has been shown to drop as much as 20 percent. Stay hydrated all the time! Carbohydrates – ―Carbs‖ have been getting a bad rap lately, and that’s probably mostly due to marketing of diet fads and foods (Atkins diet etc). Carbohydrates are divided into two categories 1) simple carbs (sugars – lactose, sucrose, fructose, and glucose); and 2) complex carbohydrates, which are sugar molecules linked together. Your body takes all carbohydrates and converts them to glucose, which is absorbed into the blood, heart, skeletal muscles, and liver – and in that order. Skeletal muscles and the liver can absorb glucose and convert it into glycogen for storage and later use. Glucose not immediately needed is also converted into fat. Blood sugar levels are extremely important for proper physiological functions and also athletic performance. These levels are control by the hormone insulin. You basically want your insulin and blood sugar levels as constant as possible. The rate at which the body digests carbohydrates and sees a change in blood glucose level is represented by a metric known as the ―glycemic index‖. The higher this glycemic index, the more rapidly your blood sugar rises. High spikes in blood sugar results in an insulin surge which simulates your body to store glucose as fat. This effect on the body’s metabolism is one of the causes of the huge increase in child and adult obesity in countries (like the U.S.) since the 1980s, when corn syrup (fructose-based) began to be introduced in a large variety of foods and soft drinks. High glycemic-foods can be consumed during exercise or during post-exercise recovery. However, they should be consumed in moderation or in combination with fat and protein during all other times (when combined with fat or protein, their absorption rate is slowed).
Fat – The human body needs fat, which is composed of building blocks called fatty acids. The 3 categories are saturated, polyunsaturated, and monounsaturated. The fatty acids which are important for several body functions are called EFAs—essential fatty acids. These cannot be ―made‖ by the body and have to be consumed. EFAs are made up of omega-3 and omega-6 fats, and they are found in coldwater fishes like salmon, mackerel, sardines, and herrings. Omega-6 fats are found in raw nuts, seeds, sesame oil and soybean oil. The fats which you should eat in moderation are the saturated fats, because they raise cholesterol levels, especially LDL (bad cholesterol, versus HDL, which is ―good‖ cholesterol). Saturated fats are found in animal products and some tropical oils. Additionally, the food industry takes unsaturated oils and partially hydrogenates them (to solidify them) in order to saturate the fat. These hydrogenated fats contain ―trans-fatty acids‖, which are not well digested by the body and contribute to coronary artery disease. Partially hydrogenated fats and trans-fatty acids are found in all types of processed foods, e.g. cereals, preserved breads, cookies, crackers, and some canned products. Trans-fatty acids are so bad for you that beginning in January 2006, the federal government will require all food companies to list the amount of trans-fatty acids in their products. A good example of how to avoid trans-fatty acids is to buy natural peanut butter instead of ―normal‖ peanut butter, which contains them. Bottom line – avoid any food products which contain the word ―hydrogenated‖ in the nutritional information. Polyunsaturated fats are found in corn, soybean, canola, and sunflower oils. Some of the polyunsaturated oils do contain essential fatty acids. Polyunsaturated fats may lower total cholesterol but large amounts of these fats may also lower HDL or good cholesterol. Monounsaturated fats are also good for you, and are found in nuts and some vegetables, and also in the oils of those foods, such as almond, canola, and olive oils.
Protein – You need protein for muscle growth and development. But most people take in too much protein – and leftover protein is converted to fat and sugar. Excess protein also taxes the kidneys and liver and results in more urination, which in turn increases vital mineral loss and dehydration. Protein intake should be around 1.5 to 2.0 grams per kilogram of body weight – so a 70 kg person (154 lbs) should consume between 105 to 140 gms per day. Use the high end of this range when you are training hard, trying to build muscle mass, or very long (over 3 hours) of exercise. Tuna and other fish are good sources of protein, as well as meats from free-ranging cattle and poultry. It is important, especially for female athletes, to eat protein at every meal. Micronutrients – these are vitamins and minerals. These nutrients are necessary for a wide variety of body functions, including metabolism regulation, energy conversion, body fluid regulation, and the maintenance of healthy nerve function. Deficiencies in vitamins and minerals have been linked to cancer, cardiovascular disease, osteoporosis, and anemia. Important vitamins, in particular, are vitamin E and C,. The two most important minerals are calcium and iron. You need calcium for bone strength (ie, not getting osteoporosis). You can get calcium in dairy products, tofu, fortified orange juice, soymilk, and canned fish with bones. Iron is needed for oxygen transfer to muscles and is found mainly in the blood. Menstruating women lose blood and thus iron each month and particular attention to proper iron intake is required. The best sources for iron in your diet are red meat, eggs, and beans. An endurance athlete will produce, because of intense exercise, free radicals (molecules with an oxygen atom carrying a negative charge). These free radicals will ―attack‖ other molecules to obtain another electron. This oxidation process will damage proteins, DNA/RNA, fatty acids, carbohydrates, and other important cellular components. This damage from free radicals is a key component to aging, cancer incidence, joint inflammation, and increases in LDL. The good news is that aerobic (low intensity) exercise enhances antioxidant enzyme systems which reduce the bad effects of free radicals. Additionally, antioxidants and phytochemicals, which are in fruits, vegetables, grains, and legumes, have been found in recent years to reduce the risk of a number of diseases, including cancer, heart disease, diabetes, and high blood pressure. These substances show that whole foods are important because dietary supplements cannot supply all of these, and we still don’t know what the complete table of antioxidants and phytochemicals are. This is one of the reasons a good diet should contain a wide variety of minimally processed foods. Good sources of antioxidants are: (source: Dr. James H. Willis) Blueberries, broccoli, cabbage, brussel sprouts, cauliflower, carrots, cranberries, grapes, tea (green tea more than black, and decaf tea has much less antioxidants), soy, tomatoes, culinary herbs, chocolate (dark better than milk by 4:1, moderation required!), coffee, dark beer (clear lagers have much less and no, I am not making this up), spices (cinnamon and cloves) How Much of What? If you are satisfied with your current diet, and meets the above guidelines of a healthy diet, great! However, if you would like to fine-tune your diet, or want to make sure you are getting the right amount of macro and micronutrients, here are some basic thumbrules: How many calories? Daily caloric intake should equal 30 cal per kg of body weight. (to convert your body weight to kg, divide lbs by 2.2) For a 154 lb person (70 kg), this means 2100 calories. Then modify this number by applying the following: If you add a highly active lifestyle, add 100-300 calories. If you have a sedentary lifestyle, subtract about 100 to 300 calories. If you workout, use the following factors: (use the higher end as the intensity of the workout increases) Swimming: .13 to .16 cal/min per kg of body weight Cycling: .15 to .17 cal/min per kg of body weight Running: .14 to .29 cal/min per kg of body weight. Strength training: .1 cal/min per kg of body weight
For example, if the 154 lb person leads an active lifestyle and does a hour-long hard run workout, his daily caloric needs would be: 2100 + 300 + (.29x60x70) = 3618 calories If you want to lose weight, decrease your daily caloric intake by 200-300 cal per day, but maintain at least 1500 calories (assuming your weight has been constant). This will result in a slow but healthy weight loss. For another approach, you can measure your RMR, or resting metabolic rate, at the Stuttgart Wellness Center. Make sure you follow the following rules before the measurement – no alcohol within 48 hours, no food within 4 hours, and no caffeine within 6 hours. This RMR number is the caloric requirement you need just to live. Then add any calories you would use in a workout. Where should you get the calories? The recommended range for improving health and athletic training for macronutrients are: Carbohydrates: 40 – 65% of your total calories Fat: 15 – 30% of your total calories Protein: 15 -- 30% of your total calories If you are training at higher intensities (threshold or above) or long workouts (greater than 90 min), your body needs more ―carbohydrate fuel‖ and you should be at the high end of the carbo range (65%). Keep carbo consumption in the middle of the range when training at easy or marathon pace. If you are trying to lose weight, consume carbohydrates at the low end of the scale, e.g. 40% carbos, 30% fat, and 30% protein. Note that you can use the nutritional database in the Training Peaks log to give you your daily caloric intake and percentages of macronutrients! To convert grams of macronutrients to calories, remember that: 1 gram of carbohydrate or protein contains about 4 calories 1 gram of fat contains about 9 calories 1 gram of alcohol contains about 7 calories (basically ―empty‖ calories) The optimum diet for an individual will vary from person to person, using the above guidelines, since there is a genetic factor involved. You should ―experiment‖ with the ―mix‖ of macronutrients to determine the optimum diet for the particular training phase you are in. Make sure you give a diet at least 3 weeks to adapt before you pass judgement on it. But don’t make major dietary changes unless you are at the beginning of a training season! Summary: (some key rules to eat and live by) 1. Eat smaller amounts more often. This will keep your blood sugar more constant and help control your appetite, therefore reducing the size of the main 3 meals. Frequent eating also helps keep your metabolism higher, thereby burning more calories. In addition to your normal meals, I would recommend a mid-morning snack, a mid afternoon snack, and perhaps a small snack before bedtime if you’ve had an early dinner. Make sure you keep the portion sizes small! 2. Watch the type of carbohydrates you eat – limit the high glycemic index foods (starches and sugars) to during and after long/hard workouts. 3. Get most of your calories from lean proteins, whole fruits, and fresh vegetables. 4. Get a good breakfast, which should be a mix of carbs, protein, and fats. This will make sure your body isn’t burning protein (ie, muscle) for energy from the long overnight absence without fuel, keep your metabolism high, and keep you alert. 5. Supplement your diet with a multivitamin pill, and antioxidant complex (unless you are eating a good variety of fruits and vegetables, which is the best way to get your antioxidants). If you have trouble consuming a good post-workout meal, consider making a protein shake with a supplement such as Endurox R4, or the Met-Rx Total Nutrition drink mix. Additionally, consider a calcium pill and iron pill (especially for females).
6. Stay hydrated. Keep your muscles and connective tissues loose and lubricated! If you are going to drink soft drinks, keep the amount of them reasonable and stay with diet drinks rather than the non-diet soft drinks, which are full of high-fructose corn syrup. 7. Avoid processed starches such as boxed cereals, white breads, white rice, and instead consume whole-grain breads, brown rice, unsweetened grain-based cereals, wholewheat pastas. And minimize the trans-fatty acids.
Diet Tips (if you are trying to improve your body composition): 1. Eat smaller portions, more often through the day. 2. Get rid of unhealthy foods (e.g. high glycemic index, processed foods, or trans-fatty acid snacks) 3. Give yourself a ―treat‖ of your favorite food during or after your long workout. Eat them slowly. Try to eat this within 30 min of your workout, however. 4. Reduce your serving sizes, wait 5-10 minutes between servings, eat more slowly than usual. Your body takes awhile to reduce its ―appetite‖ after eating. 5. Increase intake of high fiber foods which are low in calories. 6. Don’t weigh yourself often – it’s a short term focus. Athletes who obsess over their weigh will tend to underhydrate and skimp on recovery nutrition. After a workout, you’ve burned fat and you need food and water to replenish your glycogen stores, rebuild damaged muscles, and restore hydration. If you don’t do a good post-workout meal, you won’t be able to train as much and you will then not burn as much fat, etc etc. The important thing is how you feel and how you perform. You will arrive at the optimum weight and body composition over the long-term by following good nutritional guidelines. 7. Avoid processed starches such as boxed cereals, white breads, white rice, and instead consume whole-grain breads, brown rice, unsweetened grain-based cereals, wholewheat pastas. And minimize the trans-fatty acids! For example, don’t eat processed peanut butter – it is chock full of trans-fatty acids. Eat natural peanut butter instead. 8. Keep a meal log, especially at the beginning of your weight loss period, in order to determine how many calories and percentages of carbs, fats, and proteins you normally take in daily. Then compare this number to your calorie ―burn‖ rate calculated by adding your RMR, your lifestyle factor, and any workout calories that day. If the average ―burn‖ rate exceeds the ―intake‖ rate, you will eventually reach your natural (and healthy) weight! A good automated (and free) meal log/counter can be found at SparkPeople.com
References: Bernhart, G. Training for Multisport Athletes. Boulder, Colorado; Velo Press 2000. Daniels, J. Daniels’ Running Formula. Champaign, Illinois; Human Kinetics 2005. Verstegen, M. Core Performance. Rodale Press 2004. Friel, J., and Byrn, G. Going Long. Boulder, Colorado; Velo Press 2003