Methodology
How TPF actually works.
Most lifters hit a point where they’re doing everything right on paper — and still not sure if it’s working. TPF runs on real exercise science. How a set actually credits toward weekly volume, how fatigue accumulates across the week, how much is enough and how much is too much — none of it is guessed. The science does the bookkeeping. You make the calls that matter.
The principles are few.
Hypertrophy and strength aren’t a mystery. Apply the right stimulus, recover, push the load up, keep showing up. Four principles. The methods you build out of them are infinite — the principles themselves barely change.
Most of what you’ll read online is over-simplified, misapplied, or made artificially black-and-white. That’s where most lifters get stuck. TPF encodes the principles. You pick the methods.
How we know it works.
Every engine component is checked three ways.
- Against the research. Every formula and weighting traces back to peer-reviewed work on stimulus, recovery, periodisation, and energy-system physiology.
- Against real coaching practice. We run mainstream protocols through the engine and verify the outputs match what those protocols are known to produce.
- Against the maths. Worked examples computed by hand. If the engine drifts, we investigate and recalibrate — or document why.
What the engine actually does.
Strength & hypertrophy
The TPF Effective Sets™ system credits every working set on what actually drives growth — how close to failure you went, how heavy you lifted, how long you rested, and which muscles each lift really trains. Compounds count differently from isolation. Stretch position counts differently from short. Volume landmarks (the floor, the sweet spot, the ceiling) are tuned to your training age — not pulled from a textbook.
Strength and hypertrophy don’t grow on the same curve. The engine knows it — separate dose-response models for each, anchored to the Schoenfeld 2017 hypertrophy meta-analysis and the Ralston 2017 strength meta-analysis, and scaled to your experience level. Beginners need less to grow and recover faster than trained lifters — and the engine treats them differently.
Intensity techniques — cluster sets, myo-reps, rest-pause, lengthened partials, 1¼ reps, drop sets — each earn their own honest stimulus-to-fatigue weighting. Lengthened-bias work gets the stretch bonus the recent partial-ROM literature (Kassiano 2022, Wolf 2024) supports.
Recovery cost
Every set adds to a running fatigue total, weighed against the capacity that comes with your training age. Daily and weekly views colour the picture green, amber, red — sustainable, high, over the line. Built on the Banister fitness-fatigue model (1991) and the Foster session-RPE literature (2001+).
What we don’t claim.
- We don’t predict injury. We flag sudden spikes in load. We don’t pretend to know when you’re going to get hurt — the evidence for that just isn’t strong enough.
- We don’t replace a coach. A coach who knows you, your life, your stress, and your technique is irreplaceable. Use both if you can.
- We don’t model what we can’t see. Sleep, food, life stress, technique, genetics — those stay with you. You know your context better than any app does.
The plan you’ll do is the plan that works.
TPF hands you the engine and steps back. Pick the lifts you’ll actually do, on a schedule you’ll actually keep. The science counts the load. The calls stay with you.
Be your own expert.
Want to see the papers? Every weighting and curve in the engine traces back to the literature on the research page.