Fuelling around your cycle
If part of your cycle leaves you more tired than normal, StemNotes raises your carbs on those days.
It's for riders with Biological Sex set to Female in Settings › Profile Details. Female riders get the questions during setup. You can set them up or change them any time in Settings › Menstrual cycle.
Set it up
Your cycle. "Do you feel excessive fatigue during any phase of your cycle?" Answer No, More than normal, or A lot more than normal.
When does it happen? Set how many days before your period the tiredness starts, and how many days it lasts. Count the first day of your period as day 1. It starts at 2 days before and 5 days from day 1.
Your cycle details. Your cycle length, your period length and when your last period started, within the last 60 days.
Answer No and setup moves straight on. You can skip any step, which counts as No.
What changes in your plan
Your answer | On days in your fatigue phase |
|---|---|
No | No change to your fuel plans |
More than normal | Carbs one step higher |
A lot more than normal | Carbs two steps higher |
One step plans each block as if you were riding it 5% of your CP harder. At a higher intensity more of your energy comes from carbohydrate, so every feed gets a little bigger. Your gut limit still caps the plan.
Here's how the timing works with the starting settings. If your period starts on Fri 9 Oct, your carbs go up from Wed 7 Oct to Tue 13 Oct.
Where you see it
On the Fuel Calendar, sessions in the phase carry a "Cycle · increased fatigue" chip (one step) or "Cycle · heavy fatigue" (two steps).
The fuel plan says "Fatigue phase: carbs raised one step" (or two steps).
Settings › Menstrual cycle shows your next phase, or the date your current one ends.
Your Karoo, Garmin Edge, Garmin watch and Apple Watch get the raised plan.
Log your period
Go to Settings › Menstrual cycle › My period started and pick Today, Yesterday or Another day. Your next fatigue phase and your fuel plans update straight away. On the day StemNotes expects your period, it asks "Did your period start today?".
Once you've logged a few periods, StemNotes learns your cycle length from your last three cycles. Cycles shorter than 21 days or longer than 45 days don't count, because a long gap usually means a period went unlogged. If you log a start within 10 days of one already in the log, it replaces the old one. To remove a wrong entry, tap Remove next to it in the Period log.
Reminders
StemNotes sends two cycle notifications:
"Fatigue phase starts tomorrow", the day before.
"Did your period start today?", on the day your period is due.
Switch them off with the Cycle toggle in Settings › Notifications.
Turn it off
Settings › Menstrual cycle › Turn off cycle adjustments. Your plans go back to normal.
Your data
Your cycle settings and period log stay on your phone. Your Karoo, Garmin Edge and Garmin watch can't read your phone, so for them StemNotes sends one thing: which of the next 21 days get extra carbs, and by how many steps. Deleting your account clears all of it.
Why we have added this feature
At the moment, the research around the individual impacts of menstrual cycle on exercise performance and carbohydrate utilization are fairly limited. Some research suggests that the menstrual cycle has no significant impact on substrate utilization, but those studies tend to look at a population average rather than individual differences.
So rather than assuming all women are the same, we asked the riders testing StemNotes as well as a host of riders coaching in cycling. The consensus was that during particular phases of the menstrual cycle, fatigue was increased and rate of perceived exertion relative to intensity increased. During these periods, which occurred at different phases in different rider’s cycles, an increase in carbohydrate intake reduced the RPE or sessions while reducing the fatigue post session. It may be purely psychological, or placebo, but the fact is it worked and we weren’t going to ignore that.
This is why we give riders the option to log their cycle length, and at what phase fatigue is increased beyond baseline, or increased significantly. This then changes the carb intake suggestions to hopefully reduce the increase in fatigue and session RPE incurred during these phases of the cycle.