Gabrielle Lyon (physician (do)) and Mike Israetel (sport physiologist (phd)) side by side: how they train, eat, supplement and sleep, how strong the evidence is, and how to build a plan from either or both.
Training splits are our estimates from each expert’s published routine. Following checked October 2026.
The key differences
Lyon puts more of the week into intervals: about 15% against 5%.
In plans in their style, both use 1-minute intervals for hard sessions.
We rate the evidence behind Lyon's protocol higher: strong, against solid for Israetel.
Supplements that go into a plan: Lyon, creatine monohydrate; Israetel, none (food first). Prescription items and personal stacks stay out of every plan.
Only Lyon has a mobility or movement routine of their own.
Protocols side by side
Each line is rated for the evidence behind it. “Doctor only” items never go into a plan.
Training
Gabrielle Lyon
Resistance training 3–4 days a week, done with focusStrong evidence
1–2 days a week of short, higher-intensity intervalsSome evidence
Steady aerobic work, such as a 30-minute session or a brisk walkStrong evidence
Move after meals: a walk, some air squats or a short bodyweight circuitSome evidence
For older adults who do nothing yet, any regular resistance training is the priorityStrong evidence
Mike Israetel
For the average person, about 30 minutes of training twice a week gives the best return on time.Some evidence
After 40: most sets in the 10–20 rep range, some at 20–30, and 5–10 reps only rarely, because heavy low-rep sets raise the risk of injury.Some evidence
Train each muscle twice a week, starting with 1–2 hard sets per muscle per session, and add a set the next week if you recovered well.Some evidence
Lower the weight slowly and pause for 1–2 seconds at the bottom.Some evidence
Warm up more: three warm-up sets (light, medium, heavier) before the first working set, and 1–2 before each later exercise.Personal habit
Add weight in small steps: rarely more than about 2.5 kg or one rep per set at a time.Personal habit
Choose joint-friendly exercises with a high stimulus, for example a hack squat instead of a heavy back squat.Some evidence
Take a planned easy week every 4–6 weeks, and a lower-volume month about every 5 months.Personal habit
Eating
Gabrielle Lyon
About 2.2 g per kg of ideal body weight a day (she also gives 1.2–1.6 g per kg, sometimes up to 1.8 g per kg)Some evidence
30–50 g of high-quality protein at the first meal, and a similar large dose at the last mealSome evidence
About 2.5 g of leucine (roughly 30 g of quality protein) per meal, and about 9 g of leucine across the daySome evidence
People eating mainly plants may need more total protein, around 1.6 g per kg, because plant protein is lower quality per gramSome evidence
For inactive people, about 130 g of carbohydrate a day, roughly 40–50 g per meal, with more after exercisePersonal habit
Older adults should avoid long fasts, which can speed muscle lossSome evidence
Mike Israetel
If you want to gain muscle, only gain weight when you are lean: about 0.25 kg a week for 4–8 weeks, then a fat-loss phase.Personal habit
Stay under about 20% body fat while gaining, come back to about 15% afterwards, and get blood tests after gaining phases.Personal habit
Supplements
Gabrielle Lyon
Creatine supports muscle; she mentions possible brain benefits at higher dosesSome evidence
Prefer complete protein foods over leucine alone; amino acid supplements make most sense when a meal is low in proteinNote
She regards the official leucine allowance (about 2.7 g a day) as too low because it was based on young menNote
Mike Israetel
No specific guidance in what we reviewed.
Weak spots to know
Gabrielle Lyon
Her daily target of about 2.2 g per kg of ideal body weight is well above the official allowance of 0.8 g per kg and the 1.0–1.2 g per kg that an expert group recommends for over-65s; whether intakes that high add further benefit for most older adults is still debated.
The 'leucine threshold' idea behind her per-meal targets and her food rankings is contested; critics such as Simon Hill argue that total protein matters more and that well-chosen plant proteins can meet needs.
Some of the foundational research she draws on, such as Layman's 2005 study, was partly funded by beef and food industry groups.
Mike Israetel
Most of his content is aimed at bodybuilders and younger lifters; advice for people over 40 is a smaller part of it.
Many specific numbers, such as when to take easy weeks or how fast to add sets, are coaching rules of thumb rather than findings from trials.
He sells training programmes and diet products through RP, the company he co-founded.
Build a plan from Lyon, Israetel or both
Your free plan shows a week of gym sessions, cardio, a day of eating, supplements and mobility, fitted to your age, time and health.
What is the main difference between Gabrielle Lyon and Mike Israetel?
Their training split differs most in intervals: Lyon about 15%, Israetel about 5% (our estimate from their published routines). Lyon's signature habit is 30–50 g protein a meal; Israetel's is 2 × 30 min, close to failure.
How much protein do Lyon and Israetel recommend?
Lyon: ~2.2 g per kg ideal weight. Israetel: No fixed target.
Whose advice has stronger evidence?
We rate the evidence behind Lyon's protocol higher: strong, against solid for Israetel.
Do Lyon and Israetel disagree?
Not directly in what we reviewed. Their differences are in emphasis: lyon puts more of the week into intervals: about 15% against 5%.
Can I combine Lyon and Israetel?
Yes. In Build my mix you choose one expert per area, for example one for strength and another for eating. Your free plan shows the result straight away.