Talk
Exercise physiology in Type 1 diabetes
Rob Andrews · Parth Narendran
EXTOD conference
Glucose regulation at rest and during exercise - the foundation session.
In clinic
Everything for the consultation in one place. Start with the Rule of ICE - insulin, carbohydrate, exercise - it works in fifteen minutes and gives the person three questions instead of a rulebook.
Teaching pathway
The Rule of ICE: insulin, carbohydrate, exercise
Three modifiable variables. Teach them in this order, and the person leaves with a repeatable pre-session check rather than a set of rules to memorise.
I
Insulin
How much is still active?
Insulin on board is the dominant variable. Exercise increases insulin sensitivity, so the same dose does more. Bolus within two hours of activity warrants a reduction - start at 50%.
C
Carbohydrate
Is any needed, and when?
General guidance is 30 g per hour of activity, scaled by intensity and duration. Fast-acting for during, slower-release before longer sessions.
E
Exercise
What type, and how long?
Aerobic tends to lower glucose; high-intensity may raise it transiently before a delayed fall; resistance work varies between individuals.
Troubleshooting
Four presentations, four responses
A practical framework distilled from the eleven-step approach. Most exercise problems in clinic present as one of these four.
Recurrent hypoglycaemia during aerobic exerciseMost common presentation. Start with insulin on board.
- Establish start glucose and trend arrow - a downward arrow at onset predicts the fall
- Reduce pre-exercise bolus (begin at 50%) rather than adding carbs first
- Add during-exercise carbohydrate for sessions beyond 30 to 45 minutes
- Review over three to four sessions before escalating changes
Hyperglycaemia during or after high-intensity workUsually physiological, not a dosing error.
- Explain the catecholamine response - this alone resolves a lot of distress
- Discourage immediate correction; it often self-resolves during recovery
- Plan for the delayed fall that commonly follows
- Check for ketones if starting above 14 mmol/L
Delayed or nocturnal hypoglycaemiaGlycogen repletion over 24 to 36 hours.
- Reduce bolus for the first two meals after exercise - begin at 50%
- Consider a lower overnight basal after afternoon or evening sessions
- Advise a pre-bed check and a small snack if trending down
- For pump users, a temporary basal reduction is often more effective than extra carbs
Avoidance - not exercising at allThe largest group, and the easiest win.
- Ask what they would do if diabetes were not a factor, then work back from that
- Set the target as confidence, not fitness or glucose perfection
- Give one activity and one ICE question (insulin, carbohydrate or exercise) to take away, not a full plan
- Signpost the Exercise Confidence Guides and peer communities
Developed by the EXTOD clinical group from the EXTOD Education programme and the eleven-step approach.
Education
Talks and webinars
Webinar
Insulin adjustment strategies around exercise
Alistair Lumb
EXTOD education
Before, during and after: practical dosing frameworks.
Tools
The same tools they use
Open these on screen during the appointment. Working through one together is more effective than describing it, and the person can find it again at home. For the sessions between appointments, Enhance-d gives you their glucose and activity data in one view, shared on their terms.
Enhance-d
Our technology partner's free app and clinician dashboard - CGM, wearable and activity data in one shareable view.
Open →
GlucoseGo
The validated pre-exercise hypo risk heatmap from the EXTOD app - glucose, duration and CGM trend. Derived in people aged 12 and over, for sessions up to 60 minutes.
Open →
Session planner
Before, during and after steps with carbohydrate guidance by intensity.
Open →
Trend arrow guide
What each arrow means before starting, by insulin regimen.
Open →
The five short guides
Five short guides written at a 12-year-old reading age, with weekly challenges.
Open →
Next
When they need more than you can give in clinic
Referral routes to specialist sports clinics, plus the flyer and QR code for signposting.