Q&A with Beth Mansfield – Part 2

Two months ago, we asked readers for their nutrition questions. We received too many to answer in one issue, so this month we’re back with two more responses from Beth Mansfield, a Registered Dietitian, Sport Nutrition & Exercise Specialist with Peak Performance. Beth educates Canadian athletes of all levels, from recreational athletes to Canadian Olympians.

Interested in learning more about getting to the line fueled for your best performance? Check out one of Beth’s PowerFuel Sport Nutrition Workshops, which she offers on a regular basis. Click here for a link to Beth’s workshops.

Now onto the Q&A.

Q: I am a type 1 diabetic and 2013 will be my third half marathon. I’ve managed to run the first two with keeping my blood sugar under control but I am crediting that simply to chance. I was wondering if you might have any suggestions on what types of food I should be eating the few days pre-race so I can be well nourished for the race?

A: For endurance training of a moderate to vigorous nature, carbohydrates are your body’s major source of energy – whether you are diabetic or not. Yes, we also use fats for fuel but it is the rather limited storage of carbohydrate that becomes the issue when we start to push our bodies to go farther and faster. Your muscles and liver store carbohydrate – only a limited amount – and this needs to be continually replaced or you are not going to be able to continue to exert yourself. To maintain your supply of muscle energy for as long as possible for endurance sports such as skiing, running and cycling, follow an eating plan that includes plenty of carbohydrate rich foods. Use a sports drink during training sessions to keep blood sugar levels topped up and eat a carbohydrate rich snack after each training session when your muscles are most receptive to refueling their depleted carbohydrate stores. You will have to make sure that your insulin is adjusted appropriately.

I cover these fueling basics in a blog post on the Power of Carbohydrates. Check out that post for two handy tables that will help you calculate your daily carbohydrate needs and then figure out what foods will help you powerfuel your plate.

Q: Hi Beth, I am a female long distance runner and triathlete and sometimes suffer from lower iron levels. I am not interested in iron supplements. What kinds of foods do you recommend from a nutrition perspective to help keep my iron levels up, particularly in peak training periods? Thank you.

A: A common nutritional issue (particularly for women) is low iron stores leading to iron deficiency and iron deficiency anemia. This may make you feel weak, too tired to train, and irritable. The good news is that iron deficiency is totally preventable. The bottom line is to eat iron rich foods to maintain and/or attain optimal iron stores in your body.

Dietary Iron – Absorption is Key

To maximize your absorption of iron choose foods with higher iron content more often (the clue here is to choose the more colorful foods, such as dark green veggies, ruby red meats, brown whole grains). Eat iron containing plant foods with meat, poultry or fish and/or with Vitamin C rich foods to enhance iron’s absorption. Examples include tomato meat/bean sauce for spaghetti, a bowl of iron-enriched cereal with strawberries or beef sirloin strips and spinach with orange slices. If you are taking an iron supplement do not take it at the same time as a calcium supplement as the iron will not be readily absorbed.

Beth Mansfield is a Registered Dietitian, Sport Nutrition & Exercise Specialist with Peak Performance