It decreases the risk of heart disease, stroke, atherosclerosis, diabetes, hypertension, obesity and cancer (American Dietetic Association [ADA] 1997). No, it isn’t the latest pharmaceutical wonder or a breakthrough supplement being hawked on late-night infomercials. You may be surprised to learn that this mystery elixir is actually a vegetarian diet!
It wasn’t so long ago that such a diet conjured up images of tie-dyed hippies in some remote commune crunching on fruits, nuts and granola. Now people from all walks of life are jumping on the vegetable bandwagon. In fact, 7 percent of the American population, or 12.4 million people, are currently vegetarians (Kleiner & Greenwood-Robinson 1996). Many of your own clients who are recreational or competitive athletes may have already made the dietary switch or may be considering doing so in the future.
When people start trading in their hamburgers for veggie burgers, they worry about meeting their nutrient needs. New evidence shows that a properly planned vegetarian diet can be healthful and nutritionally sound (ADA 1997; Dwyer 1999). But what about athletes who have unique and additional strength and stamina needs? This article will show how, with a little planning and lots of variety, vegetarian diets can not only meet an athlete’s nutrient needs but also improve athletic performance. You’ll learn why high-carbohydrate, low-fat vegetarian diets just happen to be the perfect recipe to fuel working muscles (Houtkooper 1992; Nieman 1999).
What Is a Vegetarian?
Put in simplistic terms, a vegetarian is someone who consumes a plant-based diet and avoids animal flesh. Within this broad definition, there are different types of vegetarians who differ in their choice of food restrictions. The most common categories are:
- vegans: the most restrictive vegetarians, who consume only plant foods and exclude
all animal products
- lactovegetarians: who eat dairy products but avoid eggs and other animal products
- lacto-ovo-vegetarians:who eat dairy products and eggs but exclude all other animal flesh
- semivegetarians:who consume primarily a plant-based diet supplemented with some
combination of dairy products, eggs, fish and poultry but avoid red meat (ADA 1997)
Although vegetarian diets can vary widely, the exclusion of meat and/or dairy products can result in a deficiency in calories, protein, calcium, iron, zinc and vitamins D and B12 . Ann Grandjean, EdD, is executive director of the International Center of Sports Nutrition in Omaha, Nebraska, where she has been researching sports nutrition and working with professional athletes for more than two decades. She cautions her clients that they can’t become vegetarians simply by removing one or more food groups. “You need to replace those food nutrients with something else,” she says. “A balanced vegetarian diet requires some thought.”
In general, the more restrictive the diet and the higher the energy demands, the more planning is needed to meet nutritional requirements. Consuming adequate calories is the first nutritional challenge that must be met for peak performance.
Calories = Energy
Whether hiking the Himalayas or strolling around the block, the body needs calories for energy. The caloric needs of active vegetarians vary widely and are influenced by climate and by the athlete’s body size and composition, age and level of physical training (Mahan & Arlin 1992). Most nutrition and exercise physiology textbooks say that to estimate daily energy requirements, you also need to take into consideration basal metabolic rate (calculated by various equations) and exercise expenditure (i.e., energy costs for specific activities). All these variables can make for quite a cumbersome formula.
Based on a review of the literature and her own research, Grandjean devised a more practical way to estimate an athlete’s caloric needs. She simply multiplies a male or female athlete’s body weight (in pounds) by one of the following numerical factors representing light, moderate or heavy activity:
Light activities include walking on a level surface at 2.5 to 3 miles per hour (mph), bowling, golfing, sailing and playing table tennis. Moderate activities include walking at 3.5 to 4 mph, cycling, dancing, running, skiing, swimming, playing tennis and lifting weights. Heavy activities include walking uphill with a load; playing basketball, football or soccer; bicycle racing; and marathon racing.
While this formula is simple, Grandjean points out, “Categorizing activity level is the difficult task because most people overestimate here. They need to look at what they are doing the majority of their waking hours to determine their activity level.”
To illustrate, take the case of Karen, a 135-pound, part-time group fitness instructor who teaches two hours of classes four days a week while working full-time as a computer programmer. According to Grandjean’s criteria and formula, Karen has a light activity level. She needs approximately 2,160 calories per day (135 x 16). Compare Karen to Julie, a 135-pound marathoner who runs 10 to 12 miles a day and weight trains four times a week, while working full-time in a day care center. Julie falls into the heavy activity category. She needs approximately 2,700 calories per day (135 x 20).
Grandjean stresses that these numbers are just estimates and some athletes require fewer calories while others need more. “Athletes may want to record their food intake to determine their actual caloric intake,” she says. Armed with this information, you can then assess their weight and exercise performance and adjust their caloric intake accordingly. See the “Vegetarian Food Guide Pyramid & Exchange System” on page 41 for the caloric content of different foods.
Meeting Caloric Needs
To best meet energy demands, athletes should consume six to eight meals per day. Small frequent feedings help supply a steady energy source and are easier on the body’s digestive system than three large meals per day. If an athlete on a vegetarian diet consistently loses weight, the caloric density of meals and snacks should be increased by adding more legumes, dried fruits, fruit smoothies (soy or milk based), grains (breads, cereals, pasta, rice), potatoes, and foods that are a little higher in fat (avocados, nuts, seeds, and foods prepared with canola or olive oil). Fruit smoothies and juices, liquid meal replacements and sports bars can also be used to boost caloric intake.
Conversely, if too much weight is gained, portion sizes of calorie-dense foods should be decreased and more fruits and vegetables introduced. Any attempt at weight loss should be made slowly (no more than 0.5-1 pound per week) and healthfully (ADA 1993). When caloric restriction is too severe and weight loss occurs rapidly, energy decreases, fatigue sets in early, the risk of injury increases, metabolism slows and exercise performance suffers.
Many low-body-weight athletes like gymnasts and wrestlers (especially women) are at the highest risk for not consuming ample calories. When inadequate calories are consumed, the body burns its own protein stores and compromises muscle building (ADA 1993). It is recommended that calories not dip below 2,000 daily; when intake drops below this threshold, it is difficult to meet nutrient needs, especially for iron and calcium (Grandjean & Ruud 1994). See the “Vegetarian Food Guide Pyramid & Exchange System” on page 41 for the caloric content of different foods.
Carbohydrates are the cornerstone of vegetarian diets, supplying the highest-quality body fuel. They are easy for the body to break down and convert into glucose (energy) for working muscles and the brain—two vital components for peak performance! Carbohydrates supply glucose for energy via the blood stream; glucose is stored in the muscles and liver as glycogen. Glycogen stores are limited in the body, and a lack of glucose can result in fatigue. It is important that all athletes consume a diet rich in carbohydrates (about 60% of total calories) to replenish and optimize glycogen stores and fuel endurance exercise.
There are basically two types of carbohydrates: simple and complex. Simple carbohydrates are sugars, such as table sugar, soda and hard candy; they are an instant form of energy. Complex carbohydrates are starches, or sugars linked in chains, such as vegetables, legumes and whole grains; they take slightly longer to produce energy. Note that fruits, though technically considered simple carbohydrates, are actually more nutritionally similar to complex carbohydrates, since fruits are high in vitamins, minerals and fiber.
Not all complex carbohydrates are considered equal; some have a superior nutritional value because they contain more fiber. For example, whole-grain breads, cereals, rice and pasta contain more vitamins, minerals and health-protective phytochemicals than their white, refined counterparts. The higher fiber content allows glucose to be broken down and absorbed more slowly, maintaining a steady stream of blood sugar for a longer time.
Meeting Carbohydrate Needs
On a daily basis, the majority of carbohydrates vegetarian athletes consume should come from the nutritionally superior, higher-fiber carbohydrates, such as whole grains, legumes, fruits and vegetables. Many experts recommend a daily carbohydrate intake of 5 to 10 grams per kilogram of body weight (g/kg BW), or 2.3 to 4.5 g/pound (Berning & Steen 1991; Coyle & Coyle 1993).
At the International Center of Sports Nutrition, Grandjean estimates vegetarian athletes’ carbohydrate needs based on activity level, as follows:
Moderate Amount: 5 g/kg BW, or 2.3 g/pound—Activities that require moderate amounts of carbohydrates include plyometrics, drills, sprints, weight lifting, skill training and any aerobic training (running or biking) lasting less than 60 minutes.
Heavy Amount: 8 to 10 g/kg BW, or 3.6 to 4.5 g/pound—Activities that require heavy amounts of carbohydrates include aerobic training lasting longer than 60 minutes.
Using this formula for the case examples cited earlier, Karen, the part-time group fitness instructor has moderate carbohydrate needs calculated as 135 pounds x 2.3 g/pound, which equals approximately 311 g of carbohydrate daily. Marathon runner Julie, on the other hand, has heavy carbohydrate needs calculated as 135 pounds x 3.6 g/pound, which equates to 486 g of carbohydrate daily.
Vegetarian athletes also need to consider their carbohydrate needs immediately prior to and after competing in an athletic event. Experts recommend that athletes consume about 100 g of complex carbohydrates two to three hours prior to an athletic event (Kleiner & Greenwood-Robinson 1996). Refined grains like bagels and white-flour pasta are the preferred choice since they break down rapidly, supplying glucose more quickly to the body. To replenish glycogen stores after an event, any type of carbohydrate should be consumed as soon as possible (40-60 g per hour during the first 5 hours after the event) (Kleiner & Greenwood-Robinson 1996).
Carbohydrate food sources include breads, cereals, pasta, rice, grains (amaranth, barley, buckwheat, bulgur, corn, kamut, millet, quinoa, rye, spelt, whole wheat), fruits and vegetables. Legumes, soy and dairy products supply both carbohydrates and protein. See the “Vegetarian Food Guide Pyramid & Exchange System” on page 41 for the carbohydrate content of different foods.
For the athlete, protein is most notably involved in building muscle. Protein is also needed to produce hemoglobin, which carries oxygen to working muscles, and to produce enzymes and hormones involved in metabolism. Additionally, protein serves as a last-resort energy source when carbohydrate consumption is inadequate (Berning 1997). In general, protein should make up about 12 to 15 percent of a vegetarian athlete’s diet. Protein requirements will vary based on exercise type, duration and intensity; fitness level; and energy intake (Slavin 1991). However, despite the fact that the current Recommended Dietary Allowance (RDA) for protein is 0.8 g/kg BW, the body of literature overwhelmingly indicates this amount is inadequate to support an athlete’s protein needs, since physical training increases the metabolism of amino acids (ADA 1997).
While no specific RDA is currently available for athletes, a reasonable daily protein intake for vegetarians would range from 1.5 to 1.8 g/kg BW and possibly even a little higher. Some experts recommend 1.2 to 1.4 g/kg BW for endurance exercisers and 1.7 to 1.8 g/kg BW for strength athletes (Lemon 1996), whereas the ADA and the Canadian Dietetic Association both recommend 1.5 g/kg BW (ADA 1993). Grandjean concurs with the ADA recommendation but adds the caveat that 65 to 70 percent of that protein should be in the form of animal protein and calories should not be restricted.
Due to the lower digestibility of plant protein (about 85% versus 95% for animal protein) (Messina et al. 1994), requirements are somewhat higher for vegetarians than nonvegetarians. Virginia Messina, MPH, RD, is a Port Townsend, Washington, based nutrition consultant and author of five books on the nutritional needs of vegetarians. “Depending on the level of exercise, protein needs for nonvegetarians could be as high as 1.5 g/kg BW,” she says. “If that is true, we have to assume that some vegans could [need] as much as 1.8 g/kg BW.” This recommendation is in keeping with recent research that suggests elite Japanese track and field athletes who consume a plant-based diet may require more than 2 g/kg BW (Sugiura et al. 1999).
Here’s how to calculate the protein needs for Karen, the group fitness instructor, and Julie, the marathon runner, using the range of 1.5 to 1.8 g/kg BW (note that 1 kg = 2.2 pounds):
Karen: 135 pounds = 61 kg x 1.5 g/kg = approx. 92 g protein per day
Julie: 135 pounds = 61 kg x 1.8 g/kg = approx. 110 g protein per day
Meeting Protein Needs
Proteins are made up of 20 amino acids, nine of which are essential amino acids (EAAs), meaning they must be obtained through diet since our bodies cannot manufacture them. Proteins are labeled either “complete” or “incomplete,” based on the number and amount of EAAs present. Animal protein—found in meat, eggs and dairy—is often referred to as complete, since it contains all nine EAAs in amounts that closely match human needs. Thus, vegetarians who consume eggs or dairy products are obtaining complete protein. According to Messina, many plant proteins, such as grains, legumes and nuts, also contain all nine EAAs but because one or more of the EAAs is in short supply, they are considered incomplete.
Protein is the macronutrient most likely to be deficient in vegetarian diets, especially in those that don’t contain any animal products. Athletes who follow a lacto-ovo-vegetarian diet usually consume an ample amount of protein, since their diet includes dairy products and eggs. With the exception of fruits, most foods contribute some protein to the diet. See the “Vegetarian Food Guide Pyramid & Exchange System” on page 41 for the protein content of different foods.
Athletes who adhere to the stricter, vegan diet may not get enough protein to meet their performance needs. According to Messina, “Vegan diets tend to be about 10 to 11 percent protein, and this may not meet needs for those athletes whose energy needs are moderate. For example, an 80 kg strength athlete might need about
120 g of protein or more. If he were consuming a typical vegan diet and eating 3,500 calories per day, his protein intake might be only about 96 g per day. So this athlete would need to make some adjustments by choosing more servings of protein-rich plant food. An athlete with higher protein needs should choose fewer servings of grains and proportionally more of higher-protein foods like legumes” (Messina et al. 1994).
To meet protein needs, vegan diets require a bit of planning. Vegans can ensure they obtain complete protein by simply combining any legume or bean dish with any grain, nut or seed. Examples of combinations that form complete protein include many ethnic dishes, such as rice and beans; pita bread and hummus; pasta with tomatoes and cannellini beans; and a peanut butter sandwich. To make matters even simpler, these items don’t need to be consumed at the same time, just over the course of a day (e.g., oatmeal at breakfast and beans for lunch). If low protein intake is an issue, soy protein shakes can be added. See the list of food sources that contain protein in “Hard-to-Get Nutrients” on this page.
A great addition to any vegetarian diet is soy, because of its outstanding protein profile. The protein-packed soybean contains all nine EAAs, with only one EAA, methionine, in short supply. This makes soy a high-quality protein almost equivalent to animal products (University of California at Berkeley 1992).
Vegetarian athletes should try to consume one or more servings of soy on a daily basis. It has never been easier to include soy: It can be consumed as soy milk, soy cheese, soy meat analogs (soy dogs, turkey, ham, sausage, pepperoni, etc.), tofu, tempeh, soy nuts or butter, soy flour, soy cereal or soy yogurt; and as textured vegetable protein. Whenever possible, it is best to choose organic products since soy is sometimes heavily treated with agricultural chemicals (Weil 1997).
Focus on Fat
Like their meat-eating counterparts, vegetarians should consume approximately 30 percent or less of their daily nutrients from fat. The greatest contribution fat makes to sports performance is as a concentrated energy source. Although it is not yet clear how the different types of fat specifically affect sports performance, there is plenty of evidence indicating how particular fats affect health (Reade 1998). Saturated fat and trans fat should be kept to a minimum due to their negative impact on heart health.
In vegetarian diets, saturated fats can be found in whole-milk dairy products, butter, palm oil and coconut oil. In lacto-ovo-vegetarian diets, whole-milk dairy products should be replaced with reduced-fat varieties. Trans fat is found in margarines and in processed and prepared foods made with “hydrogenated” vegetable oils; it should be avoided whenever possible.
The good news is that vegetarian diets, particularly vegan diets, are naturally low in fat and contain mostly the unsaturated fats found in plant foods. There are two types of essential fats that need to be taken in through the diet: omega-3 and omega-6. Most people consume more omega-6 fats (found in polyunsaturated vegetable oils like corn, safflower and sunflower) than omega-3 fats (found in fish, flaxseed, hemp oil, walnuts, canola oil and dark green, leafy vegetables). Research seems to indicate that the ratio of these two essential fatty acids is vital and typically out of balance in most diets. Therefore, it is recommended that people on all types of diets strive to include more omega-3 fats and fewer omega-6 fats. Vegetarians in particular should try replacing polyunsaturated vegetable oils (and products that contain them) with monounsaturated fats like olive and canola oils; vegetarians should also eat a handful of nuts—particularly walnuts—regularly. While not to everyone’s taste, ground flaxseeds can be added to fruit juice or yogurt, and flaxseed oil dressing can be used to top a salad. (Advise clients to start with one teaspoon of freshly ground flax and gradually build up to one to two tablespoons daily. Clients should drink lots of water too!)
Micronutrients That Play Hard to Get
When any food group is excluded from the diet, other foods need to replace the lost nutrients to ensure a healthful balance. Since vegetarians exclude meat and vegans exclude all animal products and dairy, vegetarian diets can potentially be deficient in calcium, iron, zinc and vitamins D and B12 . The table on page 43 shows some practical and specific ways vegetarian athletes can ensure they get enough of these important nutrients.
Calcium is involved in bone health and regulates nerve and muscle function. It is generally accepted that one’s calcium balance can be negatively impacted by a high-protein diet, excessive sodium or phosphorus intake and lack of exercise. Recent research suggests that a high-protein animal diet causes higher excretion of calcium in the urine than plant-based diets that contain less protein (Itoh et al. 1998). Other studies have shown that the body adapts to a low-calcium diet by increasing the amount that is absorbed (Garrison & Somer 1995).
Calcium needs may be somewhat lower for vegetarians, particularly vegans, than for nonvegetarians (ADA 1997). Studies have indicated that vegan women do not have lower bone density than lacto-ovo-vegetarians, even when the former group’s calcium intake is almost 300 milligrams (mg) lower per day (Barr et al. 1998). Nonetheless, it is still advisable for all adult vegetarians to consume the RDA of 1,000 mg; those over age 50 need from 1,200 to 1,500 mg daily (Klausner 1999).
The RDA can be met by consuming at least three to four servings of calcium-rich foods daily. One thing to point out to your vegetarian clients: Although high in calcium, spinach, Swiss chard and beet greens all contain oxalic acid, which decreases calcium absorption in the body. Because there are many sources of calcium besides cow’s milk, even vegans can meet their calcium needs by eating a balanced and varied diet. If vegan athletes find it difficult to get enough calcium, they should take a supplement. Messina recommends taking calcium citrate or malate if gastrointestinal distress is an issue; otherwise, calcium carbonate is absorbed just as well. See “Hard-to-Get Nutrients” on page 43 for a list of different food sources for calcium.
Vitamin D is also associated with bone health, and most dairy milk products are now fortified with this nutrient. “Vegan athletes need to make sure they consume foods fortified with vitamin D, such as some breakfast cereals and soy milk,” advises Messina. The most recent guidelines for vitamin D are 200 International Units (IU) for most age groups, 400 IU for those over age 51 (Garrison & Somer 1995) and 600 IU for those over age 70 (Kay 1999). See “Hard-to-Get Nutrients” on page 43 for a list of different food sources for vitamin D.
Another source of vitamin D is sunlight; the ADA recommends spending five to 15 minutes per day in the sunshine without sunscreen (ADA 1997).
Iron is especially important to the vegetarian athlete since it helps to shuttle oxygen as hemoglobin in the blood and as myoglobin in the muscle. Iron is also heavily involved in the enzyme systems within the cells that produce energy (Mahan & Arlin 1992). Two forms of iron are found in food: heme and nonheme. Heme iron is found primarily in meat, chicken and fish; this form is more easily absorbed than the nonheme iron found primarily in plants. Certain substances, such as plant phytates and fiber, tannins (found in coffee and tea) and calcium, can inhibit iron absorption. ‰
Despite a diet high in nonheme plant products, vegetarians are not prone to iron deficiency. In fact, many research studies confirm that vegetarians with a well-balanced diet have adequate iron stores (Clarkson et al. 1994; Harman & Parnell 1998; Hunt et al. 1999; Sanders 1999). Vegetarians seem to experience physiological adaptations (such as excreting less feral iron) that increase the efficiency of iron absorption (Hunt et al. 1999). Without severe caloric restriction, vegetarians can easily consume the RDA of 10 milligrams [mg] per day for men and postmenopausal women or 15 mg per day for women of childbearing age. Those at greatest risk for iron deficiency are female vegetarians who restrict calories.
Vegetarian diets tend to be rich in vitamin C, which boosts iron absorption. By adding a vitamin C source to meals or snacks—for example, adding strawberries to cereal or tomatoes to a spinach salad—clients can further increase the amount of iron they take in. Some vegetables, like broccoli and bok choy, pack a double whammy: They are high in both iron and vitamin C. Vegetarians can further increase the iron content of foods, especially acidic ones like tomatoes, by simply cooking in cast-iron pans. To maximize iron absorption, vegetarians should also avoid drinking coffee, tea and calcium-rich milk (cow or soy) and taking calcium supplements when eating plant foods rich in iron (Walton 1994).
The iron content of packaged foods is listed as a percent “DV,” or Daily Value, and is based on an iron requirement of 18 mg (Center for Science in the Public Interest 1996.). If a food product states “30% DV,” a serving contains 6 mg of iron. See “Hard-to-Get Nutrients” on page 43 for a list of different food sources for iron.
Zinc is a cofactor (an essential component) of more than 20 enzymes involved in numerous metabolic processes—more than all the other trace minerals combined (Center for Women’s Healthcare 1999.). For the athlete, zinc is most notably in-
volved in the production of energy, proteins and a strong immune system.
Unfortunately, little is known about the zinc status of vegetarian athletes. In vegetarians zinc intake and bioavailability (the amount absorbed) tend to be lower than in nonvegetarians, due to the fiber and phytate found in plant foods. Nevertheless, numerous researchers have found zinc status to be adequate in both vegetarians and strenuous exercisers (Brouns 1991; Gibson 1994; Hunt et al. 1998; Mangels 1998). Zinc supplementation appears to have no positive effect on athletic performance.
The RDA for zinc is 12 mg per day for adult women and 15 mg per day for men. Vegetarians should consume legumes and whole grains daily to meet zinc requirements (Hunt et al. 1998).
See “Hard-to-Get Nutrients” on page 43 for a list of different food sources for zinc.
The B Vitamins
The B vitamins are essential for sports performance because they help produce energy from carbohydrate, protein and fat. Most B vitamins are easily obtained through a varied diet since small amounts exist in many animal and plant foods. The exception is vitamin B12 .
Vitamin B12 is essential for a healthy nervous system and for the production of red blood cells. This vitamin is naturally found only in animal products. Vegetarian diets that include dairy, eggs or some other animal products will provide adequate amounts of vitamin B12 (Weil 1995). Since it is stored in the body, only small amounts are needed. The RDA for adults is 2 micrograms (mcg).
Vegetarians who avoid dairy, eggs and all other animal products need to find other sources of vitamin B12. Messina recommends that “all vegan athletes should have a vitamin B12 supplement or consume foods that are fortified with this nutrient.” Food sources that are fortified with vitamin B12 include Red Star (T-6635) brand nutritional yeast; some soy milks and meat analogs; and certain cereals, like Grapenuts (Mangels 1999). Clients should be advised to check labels for B12 fortification. See “Hard-to-Get Nutrients” on page 43 for a list of different food sources for vitamin B12.
Antioxidants and Exercise
Vegetarian athletes may inadvertently be the beneficiaries of yet another physiological function. Recent research suggests that the antioxidant trio—vitamins C and E and beta carotene—may protect against exercise-induced “oxidative stress” (Packer 1997). When exercising, the body takes in and utilizes oxygen at a higher rate, promoting cellular oxidation. This, in turn, promotes the production of free radicals (unstable molecules), which can destroy other cells. Any brave molecule that intervenes and squelches free radicals is dubbed an “antioxidant.”
Although there is little evidence that increasing antioxidant intake can improve exercise performance (Telford et al. 1992), consuming more antioxidants does appear to decrease muscle damage and enhance immune function. Many researchers believe there are no known risks and may possibly be long-term benefits to taking the antioxidant trio in amounts exceeding the RDAs (Brainin-Rodriguez 1994; Packer 1997). While these antioxidants also show promise for enhancing recovery from exercise, more research is needed in this area. One thing is sure: All athletes should consume plenty of fruits and vegetables that are naturally rich in antioxidants—for example, strawberries, tangerines, broccoli, carrots and tomatoes. Vegetarian athletes may have the competitive edge here since their diet is already rich in antioxidants!
While there is no substitute for a varied and well-balanced diet, both Grandjean and Messina recommend that vegetarian athletes take a basic one-a-day type of vitamin and mineral supplement that meets the RDAs. However, clients should avoid supplements that contain iron unless medical tests confirm the need for additional iron. Too much iron can increase the risk of cancer and heart disease (Weil 1995).
Don’t Forget Fluids
Water is essential for good health, peak energy levels, athletic performance and life itself! Water helps keep athletes cool through the process of perspiration. To prevent dehydration, water must be consumed regularly throughout the day. Dehydration can lead to early fatigue, muscle cramping, heat exhaustion and life-threatening heatstroke.
The recommended intake for sedentary individuals is a minimum of eight to ten 8-ounce glasses of fluid daily (Kleiner & Greenwood-Robinson 1996), with at least four of those glasses as water (Welland 1999). Athletes need to drink this amount plus enough to make up for the fluids lost in exercise. Because thirst is not a good indicator of dehydration, athletes need to schedule drinks throughout the day for optimal sports performance. A good strategy is to keep a water bottle at arm’s length and sip from it constantly.
The American College of Sports Medicine recommends consuming sports drinks when exercise lasts 60 minutes or longer. These products contain electrolytes, which enhance fluid absorption and boost energy by maintaining blood sugar levels (ADA 1993). A drink containing 5 to 8 percent carbohydrate is ideal for quick energy and is easy on the gastrointestinal system (LaPiana 1998). (Carbohydrate should be in the form of glucose, a glucose polymer or sucrose; fructose is ab- sorbed more slowly and may cause gastrointestinal distress.) Sports drinks typically supply 50 to 80 calories per 8-ounce serving; those that supply less than 40 calories in the same serving size are ineffective (La- Piana 1998).
Vegetarian athletes need to drink fluids before, during and after exercise. See below for guidelines.
The Vegetarian Diet in a Nutshell
Whether your vegetarian clients are recreational cyclists or triathletes in training, it is important they consume a variety of foods and meet calorie needs. In general, a vegetarian diet for prime performance contains approximately 60 percent carbohydrate, 12 to 15 percent protein and 30 percent or less fat. However, as Messina points out, “There is room for flexibility within the overall diet. The point is to get adequate but not excessive protein and to keep fat intake moderate but not too restricted.” Grandjean cautions that “exercise performance itself needs to be evaluated. If an athlete is feeling early fatigue, carbohydrate intake should be assessed. If muscle building is not happening, check total protein intake.
American Dietetic Association (ADA). 1993. Position of the American Dietetic Association and the Canadian Dietetic Association: Nutrition for physical fitness and athletic performance for adults. Journal of the American Dietetic Association, 93, 691-6.
ADA. 1997. Position of the American Dietetic Association: Vegetarian diets. Journal of the American Dietetic Association, 97 (11), 1317-21.
Barr, S., et al. 1998. Spinal bone mineral density in premenopausal vegetarian and nonvegetarian women: Cross-sectional and prospective comparisons. Journal of the American Dietetic Association, 98 (7), 760-5.
Berning, J. R. 1997. No magic elixir. ACE FitnessMatters, 3 (4), 1-2.
Berning, J. R., & Steen, S. N. 1991. Sports Nutrition for the ’90s: The Health Professional’s Handbook. Gaithersburg, MD: Aspen Publishers Inc.
Brainin-Rodriguez, L. 1994. Antioxidants and exercise: Do they affect recovery and performance? SCAN’s Pulse, 13 (3), 1-5.
Brouns, F. 1991. Advances in nutrition and top sport. In Medicine and Sport Science. New York: Karger.
Center for Science in the Public Interest. 1996. Iron in food. Nutrition Action Health Letter (January-February).
Center for Women’s Healthcare, Weill College of Cornell University. 1999. Mineral watch: Update on zinc. Food & Fitness Advisor, 2 (3), 6-7.
Clarkson, P. M., et al. 1994. Trace mineral requirements for athletes. International Journal of Sports Nutrition, 4 (2), 104-19.
Coyle, E. F., & Coyle, E. 1993. Carbohydrates that speed recovery from training. The Physician and Sportsmedicine, 21 (2), 111-23.
Dwyer, J. 1999. Convergence of plant-rich and plant-only diets. American Journal of Clinical Nutrition, 70 (3), 620S-2S.
Garrison, R., & Somer, E. 1995. The Nutrition Desk Reference. New Canaan, CT: Keats Publishing.
Gibson, R. S. 1994. Content and bioavailability of trace elements in vegetarian diets. American Journal of Clinical Nutrition, 59 (5 Suppl), 1223S-32S.
Grandjean, A. C. 1987. The vegetarian athlete. The Physician and Sportsmedicine, 15 (5), 191-4.
Grandjean, A. C., & Ruud, J. S. 1994. Nutrition for cyclists. Clinical Sports Medicine, 13 (1), 235-47.
Harman, S. K., & Parnell, W. R. 1998. The nutritional health of New Zealand vegetarian and non-vegetarian Seventh-Day Adventists: Selected vitamin, mineral and lipid levels. New Zealand Medical Journal, 111 (1062), 91-4.
Houtkooper, L. 1992. Food selection for endurance sports. Medicine & Science in Sports & Exercise, 24 (9), S349-59.
Hunt, J. R., et al. 1998. Zinc absorption, mineral balance and blood lipids in women consuming controlled lactoovovegetarian and omnivorous diets for 8 weeks. American Journal of Clinical Nutrition, 67 (3), 421-30.
Hunt, J. R., et al. 1999. Nonheme iron absorption, fecal ferritin excretion and blood indexes of iron status in women consuming controlled lactoovovegetarian diets for 8 weeks. American Journal of Clinical Nutrition, 69 (5), 944-52.
Itoh, R., et al. 1998. Dietary protein intake and urinary excretion of calcium: A cross-sectional study in a healthy Japanese population. American Journal of Clinical Nutrition, 69 (4), 742-3.
Kay, L. 1999. Alternative & Complimentary Nutrition Therapy. Eureka, CA: Nutrition Dimension Inc.
Klausner, A. 1999. EN’s guide to calcium in unexpected places. Environmental Nutrition, 22 (5), 5.
Kleiner, S. M., & Greenwood-Robinson, M. 1996. High-Performance Nutrition: The Total Eating Plan to Maximize Your Workout. New York: John Wiley & Sons Inc.
LaPiana, K. 1998. Sports nutrition. IDEA Health & Fitness Source, 16 (April), 30-8.
Lemon, P. W. 1996. Is increased dietary protein necessary or beneficial for individuals with a physically active lifestyle? Nutrition Reviews, 54 (4), S169-75.
Mahan, L. K., & Arlin, M. 1992. Food, Nutrition & Diet Therapy (8th ed.). Philadelphia: W. B. Saunders Company.
Mangels, R. 1998. Scientific update: Zinc and vegetarian diets. Vegetarian Journal (July-August).
Mangels, R. 1999. Vitamin B12 in the vegan diet. In D. Wasserman (Ed.), Simply Vegan: Quick Vegetarian Meals (3rd ed.).
Messina, M., et al. 1994. The Simple Soybean and Your Health. Garden City Park, NY: Avery Publishing Group.
Nieman, D. C. 1999. Physical fitness and vegetarian diets: Is there a relation? American Journal of Clinical Nutrition, 70 (3), 570S-5S.
Packer, L. 1997. Oxidants, antioxidant nutrients and the athlete. Journal of Sports Science, 15 (3), 353-63.
Pennington, J. A. 1989. Bowe’s and Church’s Food Values of Portions Commonly Used (15th ed.). Philadelphia: J. B. Lippincott Company.
Reade, C. 1998. Time for an oil change? IDEA Health & Fitness Source (September).
Sanders, T. A. 1999. The nutritional adequacy of plant-based diets. Proceedings of the Nutrition Society, 58 (2), 265-9.
Slavin, J. L. 1991. Assessing athletes’ nutritional status: Making it a part of the sports medicine physical. The Physician and Sportsmedicine, 19 (11).
Sugiura, K., et al. 1999. Nutritional intake of elite Japanese track-and-field athletes. International Journal of Sport Nutrition, 9, 202-12.
Telford, R. D., et al. 1992. The effect of 7 to 8 months of vitamin/mineral supplementation on athletic performance. International Journal of Sports Nutrition, 2 (2), 135-53.
University of California at Berkeley. 1992. Wellness Encyclopedia of Food and Nutrition. New York: Random House.
Walton, E. S. 1994. Are you getting enough iron, or perhaps, too much? Vegetarian Journal (July-August).
Weil, A. 1995. Natural Health, Natural Medicine. Boston: Houghton Mifflin Company.
Weil, A. 1997. The joy of soy. Self Healing (July), 1-6.
Welland, D. 1999. Drink to good health, especially water: Here’s why and how much. Environmental Nutrition, 22 (10), 1-6.
Subscribe to our Newsletter
Stay up tp date with our latest news and products.