FortiorStrength
Bodyweight strength, measured relative to your bodyweight
On a push-up, pull-up or dip, the weight you move is mostly you. Fortior estimates the most total load you could move for one rep, then divides it by your bodyweight, so your progress stays honest when your weight changes.
Why kilograms alone mislead on bodyweight lifts
On a barbell lift, the load is the plates on the bar, and an estimated one-rep max in kilograms tracks your strength well. On a pull-up, the load is your own bodyweight plus anything you hang from a belt. That creates two problems if you track kilograms alone:
- Losing weight looks like getting weaker. Cut from 80 kg to 76 kg and do the same pull-ups, and the total load drops by 4 kg even though you did not lose any ability.
- Gaining weight looks like getting stronger. The same reps at a heavier bodyweight move more total load, whether or not your pulling improved.
Dividing by your bodyweight on the day removes that swing. It answers the question most people actually have: can I move my own body better than before?
How Fortior calculates it
Each set you log on a bodyweight exercise keeps a note of your bodyweight at that moment, taken from your most recent weigh-in. From there:
- Total load is your bodyweight plus any added weight. For assisted work it is your bodyweight minus the assistance.
- Estimated max total load is the most you could likely move for one rep. Fortior uses the same five-formula estimate it uses for other lifts, from your reps plus your reps in reserve. A blank reps-in-reserve field counts as two.
- Relative strength is that estimated max divided by your bodyweight, shown as a multiple such as 1.24× BW.
- Added-load margin is the estimated max minus your bodyweight: roughly how much you could hang from a belt and still do one rep.
A worked example
An 80 kg lifter does 6 strict pull-ups with about 2 reps left in the tank. The five formulas put the most total load they could move once at about 99 kg.
| Set | Total load | Estimated max | Relative strength | Added-load margin |
|---|---|---|---|---|
| 6 reps, 2 in reserve, at 80 kg | 80 kg | about 99 kg | 1.24× BW | about 19 kg |
| Same set after a cut to 76 kg | 76 kg | about 94 kg | 1.24× BW | about 18 kg |
| 5 reps, 1 in reserve, with a 10 kg belt at 80 kg | 90 kg | about 106 kg | 1.32× BW | about 26 kg |
After the cut, the estimated max in kilograms fell by about 5 kg, but relative strength held at 1.24×: the lifter is exactly as capable of moving their own body. The weighted set shows real progress, and it is comparable with the strict sets because both are measured against bodyweight.
Assisted pull-ups and dips
Machine or band assistance is harder to compare, because two machines can label the same help differently. Fortior keeps assisted work in its own lane, as an effective load in kilograms, and compares it only with other assisted sets. Use the same machine and setup when you can, and switch to strict or weighted sets in your log when you no longer need help.
Getting a reliable number
- Weigh in regularly. Without a current bodyweight, Fortior can still log your reps but cannot estimate load-based strength.
- Rate your effort. Reps in reserve matters as much as reps. Six reps with nothing left is a different set from six reps with three left.
- Keep sets under about 12 reps to failure. Rep-based formulas get less reliable past that, so very high-rep sets say less about your max.
- Log the variation you did. A chin-up, a wide-grip pull-up and a weighted pull-up are logged as separate variations so their trends stay comparable.
In the app: open Progress, choose Training, and look at Variation-aware performance. Bodyweight lifts show a multiple of bodyweight, such as 1.24× BW, with the change over the selected range.
Strength estimates are educational and based on your own logs. They are estimates, not tested maxes, and Fortior is not medical advice.