The 3 million Americans with Type 1 diabetes should be extra cautious when exercising, but it's certainly worth the additional effort.
Being a competitive swimmer takes a lot of discipline, and Katherine O'Malley, 15, is up to the challenge. The Wrentham, Massachusetts, teen competes both for Bishop Feehan High School, where she's a sophomore, and the Adirondack Aquatics Club, part of USA Swimming, the national governing body for the sport. Every evening, she practices at least two full hours (mornings on Sunday). And before every practice or swim meet, Katherine puts in still more work – to manage her Type 1 diabetes.
Beneath her swimsuit, Katherine wears a waterproof, wireless insulin pump called an OmniPod. The pump's settings allow Katherine and Mary O'Malley, her mother, to make temporary adjustments to the amount of insulin she continuously receives. Otherwise, the intense exercise combined with insulin could cause Katherine's blood sugar to drop dangerously low.
With Type 1 diabetes, the pancreas can no longer make sufficient insulin – a hormone essential for blood glucose, or blood sugar, control. People with Type 1 diabetes rely on regular injections of insulin to survive. Hypoglycemia – an abnormally low blood sugar level – can be caused by a reaction to insulin. Sports and exercise also affect blood sugar, and different types of activity can cause blood sugar to drop or rise.
Whether you're a young athlete competing for medals, an adult working out to stay in shape or just a kid shooting hoops with friends, if you're one of the estimated 3 million Americans with Type 1 diabetes, exercise takes extra caution and effort. But it's worth it.
Marathon Versus Sprint
NASCAR driver Ryan Reed. Olympic swimmer Gary Hall Jr. NFL quarterback Jay Cutler. Professional marathon runner Missy Foy. Mount Everest climber and Sahara Desert runner Sébastien Sasseville. Most of the professional cyclists on Team Novo Nordisk.
All compete at the highest level of sports with Type 1 diabetes.
Aaron Kowalski, 43, a diabetes researcher who leads the Artificial Pancreas Project for the nonprofit JDRF, is an avid runner who’s had Type 1 diabetes since he was 13. His younger brother was diagnosed when he was just 3 years old. Even so, both played team sports throughout school. “One of the things my parents always said to us was, ‘You’re going to do anything your friends do – or more,’” Kowalksi recalls. “’You’re going to take more care of yourself, pay more attention and maybe work a little harder, but you can do it.’” For athletes who give themselves insulin injections rather than using a pump, he says, “sometimes it takes a little more planning."
Insulin pumps deliver different types of doses. Basal insulin, which is released continuously, can be programmed to account for changes in physical activity. For endurance athletes with Type 1 diabetes, Kowalski says, a common strategy is lowering the insulin pump’s rate of infusion during exercise to reduce their risk of hypoglycemia. Blood sugar below 70 milligrams per deciliter qualifies as hypoglycemia. Bolus insulin, single doses used to cover carbohydrates in meals or snacks, may need to be cut by a certain percentage for sports and workouts.
To complicate matters, the exercise-insulin relationship “flips” with brief, intense burst of exercise such as 5-K races, 50-meter swims or ice hockey, Kowalski says. With this type of sport, “sometimes you have to take more insulin,” he says. “Because your body will ‘spill’ sugar from the liver through the stress-hormone release during anaerobic exercise.” The burst of adrenaline can lead can cause hyperglycemia – blood sugar that's too high.
Getting Swim Ready
For the O'Malleys, pre-swim meals are carefully calculated to get Katherine's blood sugar to its ideal range. "She feels good at 200 starting to swim, and she needs to be there to sustain any level of swim," Mary O'Malley says. "Especially for practice because it's so prolonged and intense and strenuous. So we usually give her at least 45 carbs before she starts to swim; and we do not cover that [with insulin] like we normally would for a regular meal." Snacks could be crackers or a banana with peanut butter, or a protein bar. At all times, wherever she is, Katherine carries glucose-rich snacks in case she needs to stave off hypoglycemia. And she monitors her blood glucose regularly.
Swim meets are busy events, packed with swimmers, coaches and parents at poolside. While Katherine is very independent and good at treating herself, Mary O'Malley is always there just in case. "Sometimes, when your [blood sugar] is really high or low, you're not your usual self and you need assistance," she says. Once at the pool, the mother-daughter team continues to tend to the young athlete's diabetes. "She usually has to get out of the pool," Mary says. "She'll go low, and she feels it in her body. She gets out; she checks her blood sugar. If she has to treat with glucose, she'll treat with glucose. And then she'll have a snack." While Katherine has never needed treatment with glucagon – a hormone injection used to raise severely low blood sugar – she's climbed out of the pool with her blood sugar in the low 20s.
Katherine competes in a variety of races: the 100- and 200-meter freestyle and backstroke are her strongest. During some races, Katherine's blood sugar can climb to a high 350 or 400. "She really doesn't swim well at that level," her mother says. "She gets a headache; she feels lethargic and she's sick to her stomach and she's just overall fatigued. Her legs will go out and she loses energy." The change is apparent both to Mary and Katherine's coach.
Facing Hypoglycemia Fear
“The fear of hypoglycemia is really the No. 1 barrier when it comes to exercise,” says Jacqueline Shahar, a clinical exercise physiologist, certified diabetes educator and manager of exercise physiology at the Joslin Diabetes Center in Boston. Common signs of hypoglycemia, also called an insulin reaction, include feeling hungry, dizzy, shaky or confused. People may turn pale, feel weak or fatigued and sweat heavily. Vision can blur. If untreated, severe hypoglycemia can lead to seizure, coma or worse. That’s why people with diabetes carry glucose tablets or gel tubes to quickly boost their blood sugar, along with simple carbs such as hard candy, raisins or juice.
For patients who stay sedentary because they fear blood-sugar lows, Shahar doesn’t just explain that exercise with Type 1 diabetes is safe – she shows them. “We take them to our gym, and we basically do an experiment,” Shahar says. “We have them check their blood sugar before they start the activity. And we can come up with some guidelines: where the blood sugar is, how safe it is, what it could be if you do this activity.” Then it’s time to give exercise a try.
“If they feel like they’re dropping – they’re not low yet but they worried about a low – we have juice, crackers, all kinds of things we could treat them with,” Shahar says. Blood sugar is rechecked during and after exercise, so patients can see trends. And they learn to adjust their insulin dosages as needed. Fear fades as they feel more in control.
Source: US News Health