Compare experts › Stacy Sims vs Rangan Chatterjee

Stacy Sims vs Rangan Chatterjee

Stacy Sims (exercise physiologist) and Rangan Chatterjee (doctor, former nhs gp) 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.

Build a plan from bothSee the protocols
Words explained (9)
Zone 2
Steady cardio at a pace where you can still talk in full sentences, but not sing.
Intervals
Short hard efforts with easy recovery in between, such as 30 seconds fast, 90 seconds slow.
Mobility
Moving your joints freely through their full range.
Creatine
A well-studied supplement that supports strength and muscle.
Omega-3 (EPA, DHA)
Healthy fats found mostly in oily fish such as salmon, herring and sardines.
Time-restricted eating
Eating all your meals within a set window of the day, for example 8am to 6pm.
Glucose
Blood sugar.
Perimenopause
The years of changing hormones before periods stop for good.
Hormone therapy (HRT, MHT)
Medicine that replaces hormones that fall at menopause. Only a doctor can prescribe it.

At a glance

MeasureStacy SimsRangan Chatterjee
BackgroundExercise physiologistDoctor, former NHS GP
Training split60% strength · 10% aerobic · 25% intervals · 5% mobility30% strength · 50% aerobic · 15% intervals · 5% mobility
Signature habitHeavy lifts + sprintsRelax · eat · move · sleep
Protein~2.2 g/kgNo fixed target
Training styleWomen 40+Lifestyle
Overall evidenceStrongSolid
FollowingInstagram 1.4M · YouTube 372KInstagram 1.7M · YouTube 1.4M

Training splits are our estimates from each expert’s published routine. Following checked October 2026.

The key differences

  • Sims puts more of the week into strength: about 60% against 30%.
  • Chatterjee puts more of the week into aerobic base (zone 2): about 50% against 10%.
  • Sims puts more of the week into intervals: about 25% against 15%.
  • In plans in their style, Sims' hard sessions are short sprints; Chatterjee's are 1-minute intervals.
  • We rate the evidence behind Sims' protocol higher: strong, against solid for Chatterjee.
  • Supplements that go into a plan: Sims, creatine monohydrate; Chatterjee, none (food first). Prescription items and personal stacks stay out of every plan.
  • Only Chatterjee 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

Stacy Sims

  • Strength training 3–4 times a week, 45–60 minutes, built on compound liftsStrong evidence
  • From perimenopause, lift heavy: about 3–5 sets of 6 reps or fewer, leaving 2–3 reps in reserve, with 2+ minutes restSome evidence
  • Sprint intervals of 30 seconds or less, all-out, with full recovery; 1–2 sessions a weekSome evidence
  • Jump and impact work (e.g. squat jumps, box jumps) for bone; one studied protocol is 10–20 jumps twice a daySome evidence
  • Keep easy cardio (walking, easy rides) as recovery; she plays down long moderate-intensity sessions and zone 2 for midlife body-composition goalsPersonal habit
  • 'Ten-minute rule': if you still feel flat after a 10-minute warm-up, scale the session downPersonal habit

Rangan Chatterjee

  • Walk at least 10,000 steps a daySome evidence
  • Strength training twice a weekStrong evidence
  • Short daily glute exercises (e.g. hip extensions), a couple of minutesPersonal habit
  • Five-minute home workout: five moves back to back, 20 s on / 40 s off for beginners or 40 s on / 20 s off for advanced, five roundsSome evidence
  • Swap any move that is too hard, painful or unsafeNote

Eating

Stacy Sims

  • Do not train fasted: about 15 g protein before lifting, plus about 30 g carbohydrate before cardio of up to an hourSome evidence
  • After training: 40–60 g protein (perimenopause on) within about 45 minutes, and carbohydrate within 2 hoursSome evidence
  • Daily protein around 2.2 g/kg body weight, the top of the 1.4–2.2 g/kg range in her ISSN position standSome evidence
  • Protein at meals 30–40 g, snacks 15–20 gSome evidence
  • Avoid long fasts, keto and big calorie cuts if active; a small deficit (about 150–200 kcal) in the evening, away from training, if aiming to lose fatPersonal habit

Rangan Chatterjee

  • Eat within a 12-hour window (for example 8am to 8pm), leaving about 12 hours a day without foodSome evidence
  • Five portions of different vegetables every dayStrong evidence
  • Around eight glasses of water a dayPersonal habit
  • Eat at least one meal a day at a table, with no phone or device nearbyPersonal habit
  • No fixed protein target in the sources we checkedNote

Supplements

Stacy Sims

  • Creatine monohydrate 3–5 g a day (start with 1–2 g if unsure), paired with strength trainingStrong evidence
  • Choose third-party tested products (NSF or Informed Sport)Note
  • Vitamin D3, omega-3, collagen and turmeric mentioned as options; no doses givenPersonal habit
  • Iron only if a blood test shows low ferritinDoctor only

Rangan Chatterjee

No specific guidance in what we reviewed.

Sleep & recovery

Stacy Sims

  • Traditional (Finnish-style) sauna at about 60–80 °C after training; she prefers heat to cold for womenSome evidence
  • If using cold water, choose cool (about 16 °C) rather than ice-coldPersonal habit
  • Treat easy days as true recovery between hard sessionsPersonal habit
  • Sees hormone therapy as a valid option for hot flushes and bone risk, but not required for every womanDoctor only

Rangan Chatterjee

  • A tech-free wind-down before bed, ideally about 90 minutesSome evidence
  • Set a cut-off for work email in the evening (e.g. 8–8:30pm)Personal habit
  • Avoid emotionally charged topics, such as money worries, late in the eveningPersonal habit
  • Get daylight or time in nature in the morning, even five minutes, to help set the body clockSome evidence

Stress & mind

Stacy Sims

  • Keep hard intervals short; she says longer efforts and very long sessions raise cortisol, already a concern in menopauseSome evidence
  • In perimenopause, have caffeine with food before training if it makes you shaky or light-headedPersonal habit
  • Listen to your own body and track responses rather than following a fixed planPersonal habit

Rangan Chatterjee

  • A daily stillness practice, starting with two minutes of meditationSome evidence
  • 3-4-5 breathing: in for 3, hold for 4, out for 5, for about five minutesSome evidence
  • One full screen-free day a weekPersonal habit
  • Before bed, write down three things that went well and whySome evidence
  • Five minutes a day enjoying natureSome evidence

Brain health

Stacy Sims

  • Creatine for brain fog and mood; she cites a trial where 5 g a day added to an antidepressant helped women with depressionSome evidence
  • Favours truly hard intervals over moderate or zone 2 cardio for midlife cognitive and metabolic benefitsSome evidence

Rangan Chatterjee

No specific guidance in what we reviewed.

Weak spots to know

Stacy Sims

  • Some researchers say her sex-specific advice goes beyond the evidence. A 2023 umbrella review co-authored by Stuart Phillips found no clear effect of menstrual-cycle phase on strength or training gains, and Sims publicly debated Lauren Colenso-Semple in 2025 on fasted training and protein timing, framed as mechanisms versus outcomes.
  • Her case against fasted training leans heavily on short-term hormone and appetite responses; critics note that longer studies measuring actual fat loss and muscle gain show little difference when daily calories are adequate.
  • Many of her menopause-specific prescriptions (exact sprint lengths, playing down zone 2, tight post-exercise protein windows) come from extrapolation and her own coaching experience rather than trials in midlife women.

Rangan Chatterjee

  • The 4 pillar approach is broad, sensible lifestyle advice, but the evidence behind specific claims is mixed; for example, a large trial found a daily eating window added no significant weight loss on top of cutting calories.
  • Some targets are round rules of thumb rather than research-based numbers: the 10,000-step goal is higher than where the benefit levels off for people over 60 (about 6,000–8,000), and eight glasses of water a day is a convention, not a tested target.
  • He has commercial ties alongside his health advice: books, an app and a paid community, and since 2023 an advisory role with Levels, a glucose-monitoring company.

Build a plan from Sims, Chatterjee 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.

Plan in Sims' stylePlan in Chatterjee's styleMix both

Questions

What is the main difference between Stacy Sims and Rangan Chatterjee?

Their training split differs most in aerobic base (zone 2): Sims about 10%, Chatterjee about 50% (our estimate from their published routines). Sims' signature habit is Heavy lifts + sprints; Chatterjee's is Relax · eat · move · sleep.

How much protein do Sims and Chatterjee recommend?

Sims: ~2.2 g/kg. Chatterjee: No fixed target.

Whose advice has stronger evidence?

We rate the evidence behind Sims' protocol higher: strong, against solid for Chatterjee.

Do Sims and Chatterjee disagree?

Not directly in what we reviewed. Their differences are in emphasis: sims puts more of the week into strength: about 60% against 30%.

Can I combine Sims and Chatterjee?

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.

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Full sources are on each profile: Stacy Sims · Rangan Chatterjee. Reviewed October 2026.