What’s the difference between physical activity and exercise?
Physical activity is any movement that uses skeletal muscles, while exercise is specific structured physical activity that involves training and developing sports skills, eg team sports, athletics and gymnastics.
Activity and blood sugar
Regular activity should be part of your child’s routine, and planning for it will help. Being active may affect blood sugar levels and you may notice changes during and after any physical activity. Regular blood sugar testing will help you to understand what being active does to your child’s blood sugar levels. Being active may cause low blood sugar levels or high blood sugar levels – or have no effect at all.
Activity may cause blood glucose levels to drop if:
- There is too much insulin working in your child’s body.
- The activity lasts longer than one hour.
- The activity is very strenuous.
Activity will cause your child’s blood glucose levels to rise if:
- Your child doesn’t have enough insulin circulating in their body.
- The activity is mostly anaerobic or competitive, for example, a football match, an athletics or any sport with multiple bursts of short, sharp, fast movement.
During physical activity
During any activity your child will use up some of the glucose that’s stored in their muscles and liver. They will need to replace these stores or their blood sugar levels may drop. This usually takes around 12 hours, but can take longer after very strenuous exercise, or if they haven’t eaten much carbohydrate.
After physical activity
After exercise, your child’s insulin will be more effective, so they may experience low blood sugar levels.You may need to adjust their insulin or food intake to prevent delayed hypoglycaemia (hypo), so talk to your paediatric diabetes team about this.
Top tips for planning physical activity
These are general guidelines, so discuss them first with your child’s diabetes team.
- Check your child’s blood sugar levels before and after activity.
- If their blood sugar levels are above14mmol/l, check for ketones. If there are ketones, don’t allow any activity until they’ve gone.
- If their blood sugar level is high before exercise without ketones, think about when your child last had insulin. They may need a small amount before exercise if it is more than three or four hours since their last injection/bolus.
- Aim for blood sugar levels of 5mmol/l or more before starting any planned activity to reduce the risk of a hypo.
- Always try to choose an injection or cannula site away from the muscles that your child is about to use (eg avoid the leg if your child’s going to play football). During exercise the blood flow to the muscles increases, speeding up the action of the insulin.
- If your child gets active within 1-2 hours of an injection or pump bolus dose, you may need to reduce their insulin dose with a meal to help prevent a hypo. If you don’t reduce the insulin, they may need an extra snack before exercise.Talk to your diabetes team about this.
- If your child exercises for 60 minutes or longer, make sure they have some extra carbohydrate during the activity.
- All children should drink when they exercise. For activity lasting less than an hour, water or sugar-free squash is fine, but for activity that lasts longer than an hour, try an isotonic sports drink, pure fruit juice (mix 50/50 with water) or ordinary ‘sugar-containing’ squash.
Going For Gold: Sports and diabetes
Having diabetes doesn’t stop your child from enjoying, and succeeding in, their favourite sport. Rower Sir Steve Redgrave – five-times Olympic gold medallist – and the all-diabetes professional cycling team, Team Novo Nordisk, prove this point. People with Type 1 diabetes can (and do) take part in most sports and activities.
Although some sports-governing bodies do have restrictions on people with diabetes, luckily this is only a few. For example, scuba diving has strict guidelines put in place for safety reasons. Contact the relevant sporting body or a local sports group for more information.
Diabetes and Exercise Checklist
Is the activity planned or unplanned?
Planned: Think about reducing your child’s insulin dose if their meal is one to two hours before the activity. Give them a meal or snack containing low fat carbohydrate, including things like pasta, baked beans, porridge, milk, yogurt and fruit.
Unplanned: Your child will probably need a carbohydrate-containing snack to help avoid a hypo. Carrying hypo treatments like glucose tablets and cereal bars is important, in case of an unplanned activity.
How soon after a meal is the activity?
1-2 hours after a meal: Think about reducing your child’s insulin dose with the meal before exercise or give them a carbohydrate-containing snack before exercising. As a rough guide, if you don’t adjust their insulin, during exercise children need at least 1g carbohydrate for every kilo they weigh.
Activity more than 1-2 hours after a meal: Your child will usually need an extra snack, such as a banana, cereal or a cake bar, about an hour before starting the activity. How much they need depends on how long they’ll be active.
How demanding is the activity?
Strenuous (eg a football match): Blood sugar levels may fall during activity, so give your child some quick-acting carbohydrate, eg sports drink, jelly sweets, jaffa cakes, and have some hypo treatment available throughout the activity.
Extended (eg a long bike ride): Your child will need a mixture of quick-acting and longer-acting carbohydrate options, such as fruit juice, sandwiches, fruit bars, crisps and biscuits. They can carry these in a small rucksack along with something to treat a hypo, such as glucose tablets.
Remember that everyone’s different – what might work for one child with diabetes, might not work for another. Balancing food intake, insulin and physical activity levels isn’t easy, and at first, will be a matter of trial and error. Have the confidence to experiment, and check your child’s blood glucose levels to see how they’re getting on. Your child’s diabetes team are also there to help.
Active parents are more likely to have active children: remember they will follow the example you set.