Five filters before calling an exercise good
| Filter | 0 points | 1 point | 2 points |
|---|---|---|---|
| Target | You cannot control the target | It contributes with uncertainty | The pattern loads the priority |
| Range | Painful or unstable range | Tolerable with adjustments | Broad and repeatable for you |
| Stability | Balance limits first | Enough stability | The target limits first |
| Progression | Poor jumps or measurement | Approximate progression | Precise load or repetition steps |
| Repeatability | Equipment or setup rarely available | Available with friction | Easy to repeat and log |
Acute pain, dizziness, loss of control or a clinical limitation is not scored; it stops the trial. This guide does not teach technique or replace an individual assessment.
Pattern matrix: options, not winners
| Pattern | Common options | Deciding question |
|---|---|---|
| Knee dominant | Squat · leg press · hack squat · split squat | Which preserves range and progression without balance taking over? |
| Hip dominant | Romanian deadlift · hip thrust · hip extension | Where can you keep control and tolerable loading? |
| Horizontal push | Barbell · dumbbell · machine press | Which variant lets the target progress? |
| Horizontal pull | Free · supported · machine row | Does the torso or grip limit before the back? |
| Vertical pull | Pull-up · pulldown · machine | Can you repeat range and load? |
| Isolation | Cable · dumbbell · machine | Does it serve a priority without repeating low-value fatigue? |
Machines and free weights can both support hypertrophy. Strength gains are specific to the trained and tested mode, so changing equipment changes the comparison. You do not need to prefer a barbell, cable or machine when another option passes the five filters more clearly.
A larger range or work at longer muscle lengths may help in some contexts, but it does not make an uncomfortable position universally required. Use a range you can control and tolerate, and do not infer exact equivalence between variants.
Test two exposures before changing
- Fix the variant
Keep equipment, grip, range and order within the workout consistent.
- Log the first reference
Save load, repetitions, RIR and any relevant limit without chasing failure.
- Repeat under similar conditions
Use comparable rest and setup for the second exposure.
- Decide
Keep it when the reference is clear; adjust or replace it when a non-target limit persists.
| Signal | Decision |
|---|---|
| More repetitions under a similar standard | Keep and progress |
| Balance repeatedly limits | Test a more stable option |
| Equipment is busy once | Use a logged alternative, not a full redesign |
| Acute pain or loss of control | Stop the set and do not force the trial |
| No comparison because variants keep changing | Freeze choices before concluding |
Supported row versus free row
If the free row ends because the lower back fatigues before the back receives a repeatable reference, a supported row may win on stability. That does not make it universally better; it fits this target and person more clearly.
When to replace and how to preserve history
| Reason | Response |
|---|---|
| Equipment is repeatedly unavailable | Save one alternative for the pattern |
| Progress is blocked by large load jumps | Find better resolution or use repetitions |
| The variant lacks a repeatable standard | Simplify setup or increase stability |
| You change from boredom every week | Keep a core and rotate only accessories |
| Pain or injury | Stop and seek appropriate assessment; do not assume equivalence |
Systematic variation can make sense, but excessive exercise replacement breaks history and makes progression harder to judge. Keep a core through a block and change for a visible reason.
BUSTAFIT stores the exact exercise, load, repetitions, RIR, last reference and history, and offers alternatives when equipment is busy or pain appears. That traceability supports a better decision than memory alone. The app does not score exercises, select a winner or claim that two variants are equivalent.