Adjusting Insulin

Adjusting
Insulin

For exercise lasting 30 minutes or longer try this:

Blood sugar changes with exercise are highly variable between and within individuals. Learn from your experiences based on:

  • Frequent self-monitoring of blood sugar levels or GCM (best and a good reason to ask to use GCM!)
  • Adjusting meal time and background (basal) insulins and
  • Use of extra carbohydrates – “excarbs”

See if this works for you:

 

Is the activity being done fasting, or more than 3 hours after your last meal?

Consider …

  • lowering your basal insulin dose
  • a carb snack
  • both!

Are you on a pump?

Up to 90 minutes before exercise, and until exercise stops, reduce basal insulin by 50 – 80% consider…

  • pump suspension when starting exercise (no longer than 60 minutes)
  • consuming more carbs as needed based on glucose monotoring

For the first meal within 90 minutes after exercise, consider consuming 1.0 – 1.2 g/kg of carbs and reducing insulin bolus by ~ 50%.

  • Reduce the risk of delayed nocturnal lows (depending on time exercise occurred) by reducing overnight basal insulin by 20% (or having a bedtime snack without insulin).

Consume additional carbs as needed (i.e 20 – 30 g/h)

Consider…

reducing basal insulin by 20% on days with prolonged activity

For the first meal within 90 minutes after exercise, consider consuming 1.0 – 1.2 g/kg of carbs and reducing insulin bolus by ~ 50%.

  • Reduce the risk of delayed nocturnal lows (depending on time exercise occurred) by reducing overnight basal insulin by 20% (or having a bedtime snack without insulin).

Can the bolus insulin given at mealtime be reduced?

Consider …

  • increasing carb intake by ~0.5 to 1.0 g per kg body mass per hour of activity.
  • depends on intensity and activity duration and blood glucose concentrations.

Reduce bolus insulin at the meal before exercise, based on upcoming activity intensity.

25% decrease -> light intensity

50% decrease -> moderate intensity

75% decrease -> high intensity

Consider …

  • lowering your basal insulin dose
  • a carb snack
  • both!

Are you on a pump?

Up to 90 min. before exercise, and until exercise stops, reduce basal insulin by 50 – 80% consider…

  • pump suspension when starting exercise (no longer than 60 min.)
  • consuming more carbs as needed based on glucose monotoring

For the first meal within 90 min. after exercise, consider consuming 1.0 – 1.2 g/kg of carbs and reducing insulin bolus by ~ 50%.

Reduce the risk of delayed nocturnal lows (depending on time exercise occurred) by reducing overnight basal insulin by 20%. (or having a bedtime snack without insulin).

Consume additional carbs as needed (i.e 20 – 30 g/h)

Consider…

reducing basal insulin by 20% on days with prolonged activity

For the first meal within 90 minutes after exercise, consider consuming 1.0 – 1.2 g/kg of carbs and reducing insulin bolus by ~ 50%.

Reduce the risk of delayed nocturnal lows (depending on time exercise occurred) by reducing overnight basal insulin by 20%. (or having a bedtime snack without insulin).

 

Overall sustained aerobic exercise needs more reductions in insulin doses and more carbs than short-term high intensity interval training. Anaerobic exercise such as sprinting or weight-lifting might even need more insulin but after you have finished – it’s complicated but you can learn from your experiences!

Let’s get more specific:

You need to decrease the amount (bolus) of rapid-acting mealtime insulin if you are planning to exercise within 90 minutes of your last meal.

 

Our suggestion

Another simple approach, if you are exercising just after your meal, is to reduce the dose by 25% and take a snack  with a low glycemic index.