For athletes

Train hard. Recover steady. Repeat.

Exercise with T1D is a physics problem nobody hands you the formulas for: cardio pulls you down, heavy lifting can push you up, and the same workout behaves differently at 7 a.m. and 7 p.m. Most apps ignore all of it. Most advice stops at "check with your doctor".

We go deeper: what's happening hormonally, how different sessions move glucose in different directions, and how to plan fuel and timing around your training instead of the other way round.

What's here for you

Cardio vs. strength: why they move glucose in opposite directions
A gym-session playbook: before, during, and after
Fueling strategies that don't wreck your numbers or your gains
What the research says about timing insulin around workouts

The muscle-building deep dive

Two guides written for lifters. One covers the practical side: training, eating, and recovering for growth when your insulin is manual. The other explains the science: what insulin actually does for muscle, where the anabolic window went, and why more insulin never means more muscle.

Start with the practical guide The science guide

Guides for this mode

All guides

AthleteTeen

A gym session playbook

A before, during, and after structure for training with T1D, so the thinking happens once instead of every session.

4 min read

AthleteTeen

Building muscle with T1D: the practical guide

Training, eating, and recovering for muscle growth when your insulin comes from a pen or pump. What changes, what doesn't, and what belongs to your care team.

9 min read

AthleteTeenT1D veteran

Cardio drops you, lifting spikes you: the why

Different kinds of exercise push glucose in different directions. The physiology explains a lot of confusing CGM graphs.

3 min read

AthleteT1D veteran

Cutting without crashing: eating below maintenance with T1D

The live question in every T1D lifting thread: how do you build or keep muscle in a calorie deficit when every low costs you the carbs you were trying not to eat? The shape of the problem, what competitors with T1D actually do, and the questions to take to your care team.

10 min read

AthleteT1D veteran

Fasted training: what the morning actually does to you

Fasted morning workouts are being sold as a cheat code for type 1. The evidence says something more useful: morning sessions are more predictable, not magic, and predictable is the whole game. What the hormones do, why lifting and cardio go opposite ways before breakfast, and what fasted even means when your basal never stops.

8 min read

T1D veteranAthlete

Fasting with T1D: Ramadan, intermittent, and everything between

What research says about fasting safely with type 1, why CGMs and closed loops changed the answer, and how to plan a fast with your care team instead of around them.

5 min read

AthleteTravelerT1D veteran

Heat, hydration and the sensor: training in summer

Heat speeds up insulin, dehydration changes what a CGM can see, and a sensor under load reads differently from a sensor at rest. When to trust the number during a hot session, when to distrust it, and why a fingerstick settles arguments.

7 min read

AthleteT1D veteran

Insulin, carbs, and muscle: the science

What insulin actually does for muscle, why running high works against you, where the anabolic window went, and the honest truth about insulin misuse in gyms.

8 min read

Newly diagnosedT1D veteranAthleteTeen

Prebolusing: why timing beats math

Rapid insulin isn't rapid. Understanding the gap between injection and action is one of the highest-leverage ideas in T1D.

3 min read

Newly diagnosedT1D veteranAthleteTravelerParentTeen

Sick days: the plan you make while you're healthy

Why a cold pushes glucose up and a stomach bug pushes it down, what ketones are telling you, and when home care stops being enough.

8 min read

AthleteT1D veteranTeenParent

Sleep, recovery and the next day's insulin

One short night measurably reduces how well insulin works the next day, in people with type 1 specifically. Why the 3 a.m. alarm night and the following day's stubborn highs are the same story, what that means for training, and why your sleep belongs in the appointment alongside your glucose.

7 min read

AthleteT1D veteran

Steroids, SARMs, and peptides with T1D: what's documented

No hype, no lecture. What research and community reports say these compounds do to glucose, what nobody knows yet, the legal reality, and what to watch.

5 min read

AthleteTeenT1D veteran

Supplements and pre-workout with T1D: what is known, which is not much

Creatine, caffeine, beta-alanine, the stimulant pre-workouts, and the protein tub. What the research actually shows for type 1, where the type 2 findings do not transfer, and why the first few sessions on anything new are sessions to watch the sensor.

7 min read

AthleteTeenT1D veteran

Training around lows: the fear, and the hours after

Fear of going low is the number one reason people with T1D train less than they want to, and the delayed low after exercise is the thing nobody explains. The mechanism, the timing, what the people who train every day actually do, and what to take to your care team.

9 min read

Newly diagnosedT1D veteranAthleteTravelerParentTeen

When insulin costs more than you have

The emergency option most people do not know exists, the $35 programs, and where to start looking. Links to the programs themselves, because only they can tell you what you qualify for.

4 min read

The app is out

Version one is on the App Store: prebolus nudges, carbs off a barcode, and your CGM history read from Apple Health. iPhone only, no account, free, and it never tells you how much insulin to take.

Get it on the App Store See what's in it