Amy Stephens

MS, RDN, CSSD, CDCES

Licensed dietiTian

specializing in sports nutrition and diabetes

Lose fat in a healthy way

lose fat in a healthy way

Lose fat in a healthy way

Why important

It has been proven that athletes with more muscle mass and less fat are able to run faster due to the power-to-weight ratio. Oftentimes, athletes will try to lose weight in an unhealthy way which can negatively affect performance and cause injury. This post reviews safe and effective strategies to lower body fat without compromising performance and mental health.

Factors influencing body composition

Genetic predisposition, age, sex, activity level, and dieting history are a few factors that affect body composition. As we age, our bodies have a greater percentage of fat tissue although studies have recently shown that can be mitigated with healthy eating and exercise. Gender is also a factor, as male athletes tend to have lower body fat composition while female-identifying athletes tend to have higher body fat.

Off season

In the off season, many athletes find themselves increasing weight. Rather than crash dieting to get back into shape, I created a guide to help decrease body fat without losing muscle or compromising performance and may cause injuries to ensue. 

lose fat in a healthy way

Performance

Running performance is based on a power to weight ratio. Increasing the amount of muscle and decreasing body fat enable an athlete to move faster through strides with less effort.  

Oftentimes, athletes will cut calories and “diet” or utilize intermittent fasting  in an effort to lower body fat and improve performance. However, these types of diets lead to depletion of glycogen and muscle mass. They are overly restrictive and the athlete often ends up regaining the weight, mostly as fat tissue which decreases performance. 

The human body needs a combination of carbohydrates, fats and protein to perform at its best. I’ve compiled a list of tips below to help athletes lose fat in a healthy way without feeling deprived, compromise performance or lead to weight regain.

Carbohydrates

During a run, our bodies are using glycogen, a stored form of glucose, as the primary source of fuel. Easy and tempo runs (VO2max 50-80%)  utilize a combination of fat and glucose for fuel. Harder track workouts (VO2max >80%) will use mostly glucose. Since our bodies are mostly using glucose for energy, replenishment after a run with carbohydrate-rich food is essential to improve training and overall fitness. Studies have shown that carbohydrates are the fastest source of energy to power a workout or run. Carbs convert into glucose at a faster rate than protein or fats and enable the athlete to run and continue running at a faster speed. Target about 5-8 grams of carbohydrates per kilogram of body weight per day (Burke).

Protein

Protein-rich foods are essential to help replenish amino acids used by muscles and repair muscle damage that occurs during eccentric exercises such as down hill running. If the diet is lacking in protein, muscle repair and growth will be negatively affected. Target 1.5-2.3 grams of protein per kilogram of body weight per day (Mettler).

Fat

Fat provides calories to support hormone production, which helps regulate many important functions in the body such as; menstruation, bone formation, or iron regulation.  It’s important to get in enough healthy fat calories to keep you full and provide fat soluble vitamins. Aim for 20% of calories from fat per day.

To convert pounds to kilograms, divide by 2.2.

All of these nutrients are critical to achieving optimal performance so careful attention needs to be made especially during weight loss efforts. Several studies have shown that crash diets don’t work and can lead to muscle loss, slow metabolism, poor mood, and decreased performance. To decrease body fat in a healthy way, follow these tips:

Tips

  1. Focus on timing of meals. Eat more food immediately before or after a run/workout and then prioritize eating a sensible meal when hungry with lots of fiber (brown rice, veggies, grilled chicken, turkey burger and salad).
  2. Increase protein to stay full. Aim for 20-30 grams of protein per meal.  Grilled chicken, sliced turkey, hard-boiled egg or edamame.
  3. Cut back on added sugars from sweets or processed foods. Too much sugar can cause a sugar crash and leave you feeling lethargic and increase hunger.  
  4. Avoid getting too hungry, as this can lead to overeating.  
  5. Keep the refrigerator stocked with fruits, veggies, lean proteins like chicken, sliced turkey, low-fat cottage cheese, hummus, low-fat plain yogurt.
  6. Snack on fruits, vegetables and small portions of nuts. Snack foods tend to be less nutritious and the calories can often add up to another meal. Add more food at meals to cut back on snacking. Use snacking as an opportunity to eat fruits + veggies.  Veggies in dip such as hummus, peanut butter or tzatziki. Rice cake with peanut butter or yogurt with fruit.
  7. Avoid weighing yourself daily. Your weight fluctuates daily from fluid shifts and seeing the scale increase and decrease can be discouraging.
  8. Aim for at least 8 hours of sleep each night because sleep allows your stress and hunger hormones to reset. Hormones like ghrelin, insulin and cortisol increase during stress which affect metabolism.  These hormones are responsible for increasing your appetite and storing fat and adequate rest will maintain an optimal balance.
  9. Allow 10% of calories to be “fun foods” or less nutritious foods (approx 200-300 calories). If you include these foods in your diet, you are less likely to crave them. 
  10. You don’t need to clean your plate every time you eat.  Restaurant portions are typically too large. Stop eating when you are full and save leftovers for later in the day or another meal.

Learn more about intuitive eating. This is a concept that focuses on hunger and satiety cues. Reconnect with how your body feels when you are hungry. Learning to slow down when eating by chewing slowly and taking breaks will help you recognize when you are full.  These simple strategies will prevent overeating. 

Sample meal plan

Breakfast

Pre workout

Oatmeal w/ banana + nuts or nut butter

Post workout

Chocolate milk, granola bar or green smoothie


Lunch

Rice bowl with grilled chicken and vegetables

Bowl of strawberries

Or

PB&J with green smoothie – banana, ice, milk, peanut butter, and spinach


Snack

Plain low-fat yogurt with fruit


Dinner

Grilled chicken, salmon or turkey burger, baked potato, salad or steamed vegetables with olive oil and lemon

Dessert – blueberries or dark chocolate


Snack (optional)

Graham crackers and low-fat milk

lose fat healthy way

References

Burke L. and Deakin V. (2015).  Clinical Sports Nutrition (5th edition).  North Ryde, N.S.W McGraw-Hill Education.

Close GL, Sale C, Baar K, Bermon S. Nutrition for the Prevention and Treatment of Injuries in Track and Field Athletes. Int J Sport Nutr Exerc Metab. 2019 Mar 1;29(2):189-197.

Jeukendrup AE. Periodized Nutrition for Athletes. Sports Med. 2017 Mar;47(Suppl 1):51-63.

Mettler S, Mitchell N, Tipton KD. Increased protein intake reduces lean body mass loss during weight loss in athletes. Med Sci Sports Exerc. 2010 Feb;42(2):326-37.

Stellingwerff T, Maughan RJ, Burke LM. Nutrition for power sports: middle-distance running, track cycling, rowing, canoeing/kayaking, and swimming. J Sports Sci. 2011;29 Suppl 1:S79-89.

Thomas D, et al. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. J Acad Nutr Diet. 2016 Mar;116(3):501-528.

Iron for endurance athletes

Iron for endurance athletes

Iron levels for athletes

Why iron deficiency is important

Iron is an important nutrient to endurance athletes because it carries oxygen and produces energy. Low levels of iron mean that fewer red blood cells are available to carry oxygen. Oxygen is essential to power muscles and the removal of metabolic waste so the body can function at peak performance. Many studies have reported the prevalence of iron deficiency in endurance athletes to be as high as 50% in females and 30% in males (Koehler 2012, Tan 2012). Although more common in female athletes, male athletes are also at risk for low iron. Often, athletes will report low energy levels or difficulty completing a workout, and later will find it’s iron deficiency. This post will review how iron impacts performance, symptoms of low iron, and how to prevent iron from impacting performance.

Iron for endurance athletes

Stages of deficiency

Dr. Peeling defined stages of deficiency and depletion (2007). What’s interesting about these stages is that iron stores can be depleted while hemoglobin levels remain within normal range. It’s not until stages 2 or 3 of deficiency that an athlete begins to see a performance impact. Before a substantial training block begins, assessing individuals’ risk factors and low iron risk factors is helpful. If an athlete has a drop in iron during a racing season, treatment can take a few weeks, which can have a detrimental impact on the racing schedule. A basic iron assessment contains the following labs:  ferritin, hemoglobin, and transferrin saturation. Your physician can order these tests and a sports dietitian can help interpret them and review best treatment options.  

> Stage 1—Iron deficiency (ID): iron stores in the bone marrow, liver and spleen are depleted (ferritin < 35 μg/L, Hb > 115 g/L, transferrin saturation > 16%). Treat with food first approach by including many iron-rich foods along with Vitamin C.

> Stage 2—Iron-deficient non-anemia (IDNA): erythro- poiesis diminishes as the iron supply to the erythroid marrow is reduced (ferritin < 20 μg/L, Hb > 115 g/L, transferrin saturation < 16%). Initiate iron supplements 65mg elemental iron. Can take 4-12 weeks to show results. 

> Stage 3—Iron-deficient anemia (IDA): Hb production falls, resulting in anemia (ferritin < 12 μg/L, Hb < 115 g/L, transferrin saturation < 16%). When levels are this low, consult with your physician about the cause and best treatment options.  

NOTE:  325 mg ferrous sulfate is equivalent to 65 mg elemental iron.

Risk factors for low iron

There are a variety of factors that contribute to low iron levels. Any one of these risk factors can cause iron levels to drop, and multiple risk factors will carry an even greater risk for low iron. Endurance athletes are at the greatest risk due to the hemolysis from the footstrike and blood loss in the gut while running and sweat.  During a training block, iron can drop 25-40% (McKay).

  • Menstruation for females
  • Low calorie intake (RED-s)
  • Endurance athletes
  • Altitude training
  • Vegan or vegetarian diets  
  • Have a history of low iron stores

Symptoms

Initially, symptoms are not overt, however, you may feel tired overtime or less of a desire to complete a workout. Most common symptoms include:  feeling lethargic, dizzy, negative mood, or poor performance (Sim).

Hepcidin

Hepcidin is a hormone released during exercise that inhibits iron absorption for 3-6 hours after a workout (Sim). This hormone regulates the amount of iron absorbed by the gut. Hepcidin levels are known to elevate 3-6 hours after a workout, thus reducing the amount of iron absorbed from food and supplements.

Iron- rich foods

There are two types of iron-rich foods – heme and non heme sources.  Heme sources are more bioavailable compared to plant-based iron sources. Up to 35% of heme versus 20% iron from plants are absorbed (Beard). An athlete can add a Vitamin C food to further enhance absorption. If iron stores are very low or you are at a higher risk for iron deficiency, you may require iron supplements in addition to dietary intervention. Currently, the RDI for iron men is 8mg and 18 mg for women.

Heme iron 

  • Beef
  • chicken
  • fish
  • turkey

Non-heme 

  • Lentils, beans
  • Chickpeas, hummus (especially if made with tahini)
  • Spinach
  • Apricots, prunes
  • Baked potato with skin
  • Enriched breakfast cereals (Cheerios)
  • Enriched pasta

Click here for a full list of iron-rich foods from the USDA database.

list of foods with iron

Sample meal ideas

Grilled chicken over rice with roasted red peppers.

Turkey sandwich on whole wheat bread with an orange.

Spinach salad with chickpeas, dried apricots, and lemon vinaigrette dressing.

Key points

Iron is an important nutrient involved with energy production and promoting oxygen uptake. Iron deficiency can negatively impact performance in athletes by reducing oxygen transferred to the cells and making the body work harder to produce energy.

Females, vegetarians, calorie-restricted diets (RED-s), endurance athletes and training at altitude increase the risk for low iron.

Symptoms of iron deficiency include fatigue, negative mood and poor performance.

Hepcidin is a hormone that reduces iron absorption for 3-6 hours following a workout. The best time to take an iron supplement or eat an iron rich meal is outside this window.

Best food sources of iron include meat, fish, poultry, dark green leafy 

vegetables. Combine iron rich foods with Vitamin C to enhance absorption.

Certain foods will compete with iron absorption, such as calcium and phytates.  

Speak with your physician or sports dietitian to help assess and treat iron deficiency.

References

Beard J, Tobin B.  2000. Iron status and exercise. Am J Clin Nutr. 72 (2):594S-597S.

Coates A, Mountjoy M, Burr J. Incidence of iron deficiency and iron deficient anemia in elite runners and triathletes. Clin J Sport Med. 2016.

Koehler K, Braun H, Achtzehn S, Hildebrand U, Predel H-G, Mester J, Schänzer W (2012) Iron status in elite young athletes: gender- dependent influences of diet and exercise. Eur J Appl Physiol 112(2):513–523

McKay, AKA, Peeling P, et al.  (2019a) Chronic adherence to a ketogenic diet modifies iron metabolism in elite athletes.  Med Science Sports Exercise.  51(3):548-555.

​​McKay et al. Iron metabolism: interactions with energy and carbohydrate availability. Nutrients. 2020 Nov 30.12(12); 3692

Ostojic SM & Ahmetovic Z. Weekly training volume and hematological status in female top-level athletes. Ahmetovic Journal of Sports Medicine and Physical Fitness; Sep 2008; 48, 3; ProQuest Nursing & Allied Health Source pg. 398

Peeling P, Blee T, Goodman C, Dawson B, Claydon G, Beilby J, Prins A (2007) Effect of iron injections on aerobic-exercise perfor- mance of iron-depleted female athletes. Int J Sport Nutr Exerc Metab 17(3):221–231

Sim et al. Iron considerations for the athlete: a narrative review. Eur J Appl Physiol. 2019 July; 119(7):1463-78

Tan D, Dawson B, Peeling P (2012) Hemolytic effects of a football-specific training session in elite female players. Int J Sports Physiol Perform 7(3):271–276

USDA database for iron rich foods