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The science

Science

The concepts LiftProof relies on, with the sources behind them. Cited literature, no inflated claims.

Reference library

Concepts the app
leans on.

LiftProof's defaults draw from the published strength literature. Every recommendation cites its source. Nothing masquerades as medical-grade certainty, and nothing here is medical advice.

  1. 01

    Rate of Perceived Exertion (RPE)

    RPE is a way to express the reps you left in reserve at the end of a set. An RPE 9 means one more rep was possible; an RPE 7 means three more were possible.

    2 citations · Helms et al. 2016 — RPE and RIR for resistance training

  2. 02

    Progressive Overload

    Progressive overload means adding something — weight, reps, sets, or proximity to failure — across sessions so the body keeps adapting.

    2 citations · Schoenfeld 2010 — The mechanisms of muscle hypertrophy

  3. 03

    Volume Landmarks (MEV / MAV / MRV)

    MEV (minimum effective volume), MAV (maximum adaptive volume), and MRV (maximum recoverable volume) are rough per-muscle weekly hard-set counts. The range between them is where productive training lives.

    2 citations · Schoenfeld et al. 2017 — Dose-response relationship between weekly resistance training volume and increases in muscle mass

  4. 04

    One-Rep Max (1RM)

    The one-rep max is the north star of strength training. Everything else — percentages, training maxes, progression math — is built on top of it.

    3 citations · Epley 1985 — Poundage Chart

  5. 05

    Periodization

    The reason you do not just add weight every session forever is that the body adapts. Periodization is the framework for managing that adaptation intentionally.

    3 citations · Rhea et al. 2002 — A comparison of linear and daily undulating periodized programs

  6. 06

    Fatigue Management

    Training is only productive when recovery keeps pace. Accumulated fatigue does not erase fitness — it hides it, and misreading that distinction leads to overtraining or unnecessary deloads.

    3 citations · Chiu & Barnes 2003 — The Fitness-Fatigue Model Revisited

  7. 07

    Reps in Reserve (RIR)

    RIR is a way to autoregulate training intensity without percentage charts — you rate how many reps you had left in the tank, and let that number steer your working weights session to session.

    3 citations · Helms et al. 2016 — RPE and RIR as autoregulation tools

Editorial diligence

How we read the literature.

  • Meta-analyses first

    When a meta-analysis exists on a topic, we cite it before citing any single study. Single-study effects often shrink when pooled.

  • Note the population

    Trained vs untrained populations respond differently. A finding on untrained college students rarely transfers to intermediate lifters cleanly.

  • No medical claims

    LiftProof is a general-wellness product. Nothing in the science section is medical advice. For health questions, talk to a qualified healthcare professional.

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