The Science Behind Pulse

Every protocol in Pulse is grounded in peer-reviewed research. We audit and update our science base every January and July.

Last updated: July 2026

Activity & Training

• Classifies activities by MET value from the 2024 Adult Compendium of Physical Activities — e.g. a riding-cart golf round (MET 3.5) counts as NEAT, walking-and-carrying (MET 5.3) as structured training.
• Autoregulates load with RPE / RIR rather than fixed percentages; rep-target framing follows Zourdos et al., 2016 (RPE-based RIR scale).
• Warm-up sets are context-aware: prescribed before heavy compound work, and safely skipped for light/accessory or already-warm movements.
• A single-modality cardio warm-up (5 min in the day's own modality) precedes cardio sessions rather than generic drills.
• Returning-user volume taper eases load back over the first sessions after a layoff (~48% → 68% → 90% of prior volume) to manage re-entry soreness and injury risk.
• Strength progress is tracked by estimated 1RM (Epley), and bodyweight-loaded exercises credit a bodyweight contribution (ExRx percentages) toward working volume.
• Deload timing is fatigue-first, not a fixed clock — triggered by strength decline, RPE creep, and skipped heavy sets, with a training-age time ceiling as a backstop (Bell 2025 review; Coleman/Helms 2024 RCT).
• Flags the ibuprofen / cold-therapy interaction with hypertrophy — high-dose NSAIDs and post-lift cold immersion can blunt muscle adaptation (Lilja 2018; Piñero 2024).

Nutrition

• Protein-first macro targets set from bodyweight and goal; the app requires a bodyweight before showing any calorie/macro target rather than guessing.
• Recomposition uses a TDEE − 250 kcal target (a modest deficit) rather than an aggressive cut, preserving training quality.
• Protein is distributed in even thirds across the day to support muscle protein synthesis, with per-window targets and catch-up nudges.
• Tracks Vitamin D, Omega-3 (EPA+DHA), and Magnesium from logged meals, food-first, with supplement suggestions only when weekly intake is below threshold.
• Omega-3 is a weekly target (2,000 mg), not daily — reflecting that intake comes in bursts from 2–3 fatty-fish meals, not a daily dose.
• Alcohol is counted at 7 cal/gram and flagged for recovery: post-exercise alcohol suppresses muscle protein synthesis by ~37% (Parr et al.).
• Caffeine guidance uses a 3–6 mg/kg performance dose and an evidence-based sleep cutoff (~8.8 h before bed for a standard cup; Burke et al.).
• Meal logging supports label scan (exact panel, incl. micronutrients), meal photo, and text — with the least-precise method flagged as an estimate.

Recovery

• Massage is recommended only when warranted — after a hard training block or during sustained high stress — reflecting that it reduces DOMS but not strength/power (Dupuy 2018; Guo 2017; Moyer 2011).
• Nap guidance is dose- and time-aware: a 20-minute power nap vs a full 90-minute cycle, ideally in the 1–3 pm circadian dip (Romdhani 2020; Boukhris 2024).
• Distinguishes heat vs cold post-lift: cold immersion right after resistance training can blunt hypertrophy, so it's steered away from muscle-building days.
• Sun exposure is credited from midday (10 am–4 pm) outdoor activity for vitamin D, nitric-oxide-driven circulation, serotonin, and circadian rhythm — non-burning exposure only (Riedmann 2025; Weller 2024).
• A fatigue engine scores sleep, soreness, RPE, and alcohol to schedule recovery walks, mobility, or rest before overreaching.

Mobility

• Stretching dose: ~3 minutes per muscle per session and ~8 minutes per muscle per week for range-of-motion gains (University of South Australia 2024 umbrella review, 189 studies).
• Foam rolling minimum: ~120 seconds per muscle group to meaningfully affect range of motion.
• Heat before stretching: 38–40 °C applied pre-stretch improves range-of-motion outcomes.
• Region-specific cues: neck uses 30-second holds (not 60); lower-back mobility targets glutes/piriformis rather than loading the lumbar spine directly.

Supplements

• Creatine: loading vs maintenance dosing, with missed days extending (never restarting) the load phase; suggested only when not already tracked to avoid doubling up.
• Vitamin D: deficiency preferentially impairs Type II (fast-twitch) muscle fibers (Wyatt et al., 2024); food-first, dosing deferred to a clinician.
• Omega-3: supports recovery per meta-analysis (Fernández-Lázaro 2024); suggested only when weekly food intake is low.
• Magnesium glycinate: supports sleep quality (Schuster et al., 2025 RCT), and is gentle on the gut before bed.

Sleep

• Treats sleep quality (not just hours) as a primary recovery input, feeding the fatigue engine and next-day training recommendation.
• Nap and caffeine timing are anchored to the circadian afternoon dip and individual sleep cutoffs rather than one-size rules.