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Exercise can feel super daunting for people living with type 1 diabetes — especially when you’re just getting started.
It might feel like simply looking at a treadmill or a dumbbell triggers your blood sugar to crash.
You start warming up, and ten minutes later — BOOM — you’re low.
Dealing with the low blood sugar means you to have to sit on the sidelines, eating calories that you are there to burn, while you watch everyone else workout around you.
There’s nothing more frustrating.
Here are three tips to help prevent lows during your next workout. Instead of fixating on your blood sugars while you exercise, you can focus on the task at hand: building strength and/or endurance.
1.) Consider the type of workout and duration of the workout you are about to do.
The first step to winning, in diabetes and in life, is having a good plan and seeing the big picture.
Understand what type of exercise you’re doing will do exactly that.
Different types of workouts tend to have different impacts on blood sugars, so your approach ahead of time can make or break the workout.
Historically, cardio workouts tend to decrease blood sugars, while strength-based workouts tend to keep blood sugars steady or potentially increase blood sugars. That increase is thanks to the liver dumping glucose into the bloodstream and your body converting lactic acid into glucose for fuel.
However, this is not set in stone. Circuit-style strength workouts have the capacity to decrease blood sugars — especially if it is a longer workout or there is very little rest time between exercises. Your body may start to see this as ‘cardio-like’ and burn more glucose for fuel — especially if you have a decent amount of insulin on board. (We’ll talk about that more in a moment.)
Lastly, the longer your workout is, the more likely you could go low. The longer the workout, the more energy is expended, which means your cells are more likely to tap into the fastest energy stores it can access– the sugar in your bloodstream
By considering the type and duration of the workout, you know if your workout is more likely to have a massive impact on blood sugar or not. The more you know, the more you can adjust accordingly to prevent exhausting lows that leave you on the sidelines.
2.) Do your best to avoid “insulin on board” going into the workout.
“Insulin on board” is the amount of active insulin you have in your bloodstream at any given moment. When it comes to exercise, the insulin you’ve taken for meals or corrections is the most risky. Why? Exercise increases the action of insulin andinsulin sensitivity. In other words, exercise makes insulin work more efficiently.
For example, if you have 1.2 active units in your body during exercise, that 1.2 units may behave more like 2, or even 3 units, which can put you on the fast track to a low blood sugar.
By reducing active insulin as much as possible, you’re reducing your chances of experiencing a low blood sugar. Some people will adjust doses for pre-workout snacks or reduce their basal rates via temporary basal or suspending to assist with this (under the direction of their care team).
How do you reduce active insulin on board?
- Exercise before you eat
- Reduce the bolus you take for a meal right before exercise
- Plan your exercise for at least 3 hours after taking a bolus of rapid-acting insulin
Remember, reducing active insulin on board does not mean exercising when your blood sugar is high. It means you’re trying to exercise with a blood sugar in your target range without a large amount of rapid-acting insulin in your bloodstream beyond your basal/background needs.
3.) Have a pre-workout snack!
This is probably the most common question I receive from the patients who come through the practice:
“What should I have for a pre-workout snack and when should I have it?”
Fortunately, it’s not too complicated: aim for a small source of carbohydrates (around 12 to25 grams) and protein (around 5 to1 5 grams) that won’t sit heavy in your stomach or take too long to digest. (In other words, don’t choose fries or a cupcake.).
To be clear: this is a small amount of carbohydrates and you won’t take insulin with this small meal. This is especially helpful during cardio exercise — or strength-training if you have a large bolus of active insulin on board.
Examples: half a turkey wrap or a piece of fruit with some string cheese.
The carbs will provide an energy source for your body to use during the workout, while the protein will help to stabilize your blood sugar and assist with preventing a low.
Now the question is when to eat it in relation to the workout.
The sweet spot tends to be about 25 to 30 minutes before your workout – not too early, which could cause a blood sugar spike, but not too late, where it could make your stomach uncomfortable as you are training.
Bonus: not only will this help keep your blood sugars more stable throughout your workout, but it might boost your workout performance, too!
Your Diabetes Insider offers these same tips to the patients who work with the dietitians and diabetes educators within the practice. Hopefully this will give you some confidence prior to your next workout so you can avoid low blood sugars and set some new personal bests!
This was a great article to help me understand why my grandson needs more protein than carbs before lacrosse. When I understand his needs, I can be more supportive by choosing the right foods to prepare. Tu😊
I have found that drinking a Glucerna shake before I play tennis has been the absolute best way to keep my sugars steady. I am 62 and was diagnosed in September so am very new to all of this. Kept crashing before tennis no matter what I ate or drank. Tried a shake and sugars held very steady for the two hours I was out there. So glad as I didn’t want to give up tennis! Thanks!
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My blood sugars were up after exercise and then crashed about 3 hours later
The exercise was 30 minutes cardio and 30 minutes weight training
Never did figure out a way around it