The Importance of Iron for Performance

Iron is one of the most essential trace minerals for athletic performance and the general population. As a college athlete, your body demands extra nutrients, including iron. According to the Academy of Nutrition and Dietetics (AND) endurance athletes, especially long distance runners, have iron needs that are 70% higher than the general population. Iron is also one of the most common nutrient deficiencies seen in athletes, especially women.

Why is iron important?
Iron is essential for energy production, metabolism and to help carry oxygen to the cells. It is also essential for growth, development and the immune system to function normally.

Common causes of iron deficiency:

• Individuals on vegetarian or vegan diets. Iron is less available in plant-based products.
• Inadequate energy intake. 
• Iron loss in sweat, feces, urine, menstrual bleeding, GI bleed, foot-strike hemolysis (with every foot strike we break red blood cells), injury, and blood donation. 
• Medical disorder that prevents absorption of iron
• Pregnancy. More demands due to a growing fetus
• Growth spurt

Symptoms of iron deficiency:

• Fatigue, irritability, shortness of breath, dizziness, headache, coldness in your hands and feet, pale skin, chest pain and weakness. 

Consequences of iron deficiency: 

• Reduced endurance
• Muscle function weakens and ability to work is limited. 
• Can lead to iron deficiency anemia, which can take 3-6 months to reverse.

Possible benefits of improving iron deficiency: 

• Improved work volume and endurance. 
• Improved oxygen uptake. 
• Decreased lactate concentrations. 
• Decreased muscle fatigue. 

How to figure out of you are deficient:

A simple blood test allows to figure if you are deficient or not. The most common test is hemoglobin. However, low hemoglobin of < 12 g/dL for women and < 13.5 g/dL for men indicates iron deficiency anemia, which will require supplementation. You can be iron deficient with no anemia. In this case, it is highly recommended to test ferritin levels. Ferritin helps store iron in the body. If it is low, we have low iron stores as well. Although the normal lab values are 12-300 ng/dL in men and 12-150 ng/dL in women, it is found that ferritin below 35 ng/dL in athletes can affect performance and supplementation may be recommended. 

How to improve iron status:

Eat a balanced diet that meets your dietary needs. Women (19-50 years) need a minimum of 18 mg of iron each day and men 8 mg. Consult your doctor or health professional about taking an iron supplement if you do not feel that you can meet your iron needs by diet alone. 

Rich dietary sources of iron: 

• The most bio-available (best absorbed) sources of iron (also called heme iron): meat, poultry, and fish. 
• Other sources (plant derived sources are not absorbed as well. Called non-heme Iron): Ready-to-eat cereal, beans, tofu, nuts and dark leafy greens. 

Tips: 

• Choose breakfast cereals that are fortified with iron 
• Choose lean meat sources (e.g. Ground beef with less than 10% fat) 
• Consume iron rich foods with foods high in vitamin C to help your body absorb the iron better (e.g. Oranges, tomatoes, red peppers). 
• Avoid drinking tea with your iron containing meals. Substances in tea reduce the absorption of iron. 
• Avoid drinking milk with your iron containing meal.
• Oxalates and polyphenols are compounds found in certain fruits, herbs, nuts, chocolate and vegetables such as: spinach, kale, tea, beets, strawberries and rhubarb to name a few, that limit absorption of iron from non-heme sources. Cooking the vegetables may assist in preventing this from occuring.  

Guest Contributor: Emily Seidl, MS, RD

Gastrointestinal Issues in Runners and Strategies to Overcome Them

Bill Rogers, a famous American runner that won four times the Boston and NYC marathon's between 1975-1980 and a 2000 USA Track & Field Hall of Famer stated, "more marathons are won or lost in the portable toilets than at the dinner table". Obviously, he was well aware of the gastrointestinal (GI) issues runners face.
GI issues have a variety of symptoms including: diarrhea, nausea, vomiting, bloating, belching, cramps heartburn and bloody stools. Symptoms are more common in women, younger athletes, elite athletes and people with a history of GI issues. It is estimated to occur in 30-90% of distance runners during and/or after exercise. Complaints of GI issues differ in severity and they may cause a decline in performance and recovery.

                           

There are three main reasons for GI problems:

• Physiological - When we exercise, depending on the intensity, blood supply to the gut may decrease by up to 80% in order to transfer more blood to the working muscles, skin and heart. This in turn may cause diarrhea, nausea, vomiting and stomach pain.
• Mechanical -   Running is a high impact sport with continuous pounding. This pounding also influences the GI tract which in turn can cause GI symptoms. Therefore, runners have a tendency to have more problems than bikers. 
• Nutritional - The meal timing before exercise as well as beverage and food choices may cause GI symptoms. A meal shortly before running, rich with fiber, fat and protein will cause GI symptoms because these nutrients have a slow emptying rate in the stomach. Drinking a concentrated carbohydrate beverage during or slightly before a race will cause GI symptoms. Moreover, dehydration intensifies GI symptoms. As discussed in the previous blog on alcohol and performance, drinking the night before a run several drinks can cause GI symptoms probably due to its diuretic effect. 
• Note; Certain people may have a medical condition such as: celiac disease, lactose/fructose mal-absorption and irritable bowel syndrome to name a few, that makes them more susceptible to GI symptoms

Since this blog is a nutrition blog, lets talk about some nutrition strategies to prevent GI symptoms:

• Hydration, hydration, hydration - before a run, make sure you are hydrated. Focus on hydrating well throughout the day. 
• Avoid beverages during or slightly before a run rich with fructose such as juice. Prefer water or if running long distance, a sports beverage with 6-8% carbohydrates such as Gatorade or Powerade.
• Avoid high fiber foods 1-2 hours pre-exercise as well as the day before a big race. 
• Avoid high fat and high protein foods 1-2 hours pre-exercise
• "Train the gut" - the gut is very adaptable, therefore, train your gut by eating during your training as well as before (if activity is lower than 60-90 minutes there is no need to eat anything during and water should suffice). Experiment with foods before a training session to check what works and what doesn't.
• Avoid using non-selective, non steroidal anti-inflammatory drugs (NSAIDs) such as Aspirin and Ibuprofen as they tend to increase GI symptoms.
• Avoid lactose containing milk products if you think or know that you are lactose intolerant. 
• Avoid or limit alcohol drinking before a morning run or a big race

It is very important that if you have severe GI symptoms such as bloody stools, you consult with a medical professional.

For specific guidance and assistance if you suffer from the symptoms noted above, consider consulting with a sports dietitian to help you with strategies to prevent any GI symptoms.

Eating for Sport - Cross Country

Long distance running is demanding on the body; not only with energy requirements, but with the toll it takes on muscles. For that reason, proper nutrition cannot be over-looked. Miles add up very quickly throughout the course of the season so having a nutrition plan to help you keep up with your nutrient needs is absolutely necessary.

Photo Credit: Women's Health Magazine

Are you meeting your energy demands? A 10 mile run could burn around 1,000 calories! A diet for runners should be comprised of mostly carbohydrate. By now, I am sure most of you have heard coaches or other people tell you to eat carbohydrates. Carbohydrates, when metabolized in the body, are converted into glucose. It is glucose that it is stored in muscles as glycogen. Your body is only able to store up to certain amount of glycogen and then it must be replenished by food after it is depleted. It is not like fat where your body has a high storage capacity.

Become familiar with foods that are high in carbohydrate. You probably already have some favorite pre-event snacks, but take a minute to look at them closely to see how much carbohydrate they actually offer you. Your carbohydrate intake should reflect how much you are training. If you doing extra training that day, eat more carbs. Your daily carbohydrate needs should be in the range of 3-4.5 grams per pound of body weight.

Protein and fat are still important in an athlete’s diet. Protein is needed to help build and repair muscle tissue. Eat approximately 0.55-0.64 grams per pound of body weight of protein per day.

Fat is needed for the absorption of some vitamins, insulation, and the production of hormones in the body. Fat should make up about 20-35% of your total calories for the day. Focus on unsaturated fats due to their added health benefits.

Being too restrictive with calorie intake will negatively affect your performance because it will not allow your body to properly fuel and refuel for your events. For women, eating too few calories can cause disruptions in her menstrual cycle. Loss of menstruation is not a normal part of training and should be discussed with a physician. The low levels of estrogen related to missing periods can impair bone mineral density, which can increase the risk for developing other health concerns such as osteoporosis.

A common nutrition concern for long distance runners, especially females, is iron. Many runners are at an increased risk for developing an iron deficiency, especially if they do not eat a lot of meat. When people suffer from an iron deficiency, they feel fatigued. But before running to the store and buying iron supplements, please seek advice from your personal or team physician. Iron supplements, like other supplements, have the potential of causing adverse effects if they are taken when they are not necessary.

Ready to head out for your long run? Choose a pre-exercise snack that, of course, is high in carbohydrate but also lower in protein, fat, and fiber. Eating foods that are high in these will likely cause some stomach upset while on your run because they take your body longer to digest. The longer time you have before you run, the larger meal or snack you can have without worry about it bothering your stomach. Don’t forget about eating after you get back! Eating a snack immediately after your run will help you replenish your energy stores. Choose a snack that is high in carbohydrate, but also offers some protein. Protein will help repair your muscles and allow you to recover more effectively before your next run. You are not done with your training until you eat your post-run snack!

As with any other sport, making sure you have adequate hydration is key to optimal performance. It only takes a 2% loss of body weight caused by dehydration to significantly impact your performance.

Hitting the Wall

As athletes, I am sure you have all heard the expression "hitting the wall." That feeling when you have nothing left to give during your workout or competition. Do you really know what is happening inside your body? 

Photo Credit: Active.com

When an athlete "hits the wall" it means that he or she has exhausted all of their stored carbohydrate (glycogen) in their body, which leaves the body running on empty. The body uses both fat and carbohydrate as fuel sources when exercising, but during high-intensity activities such as running or cycling, your body relies on carbohydrate for the main source of energy. Your body will not exhaust all of your fat stores during activity, but it can deplete your stores of carbohydrate.

This condition can by avoided by beginning your activity well-nourished with your carbohydrate stores full. During long longs or rides, be sure to take in carbohydrate through whole foods or sports drinks. The recommended amount is about 30-60 grams of carbohydrate per hour of activity.