Your first session

If you've used a force gauge with its own desktop app, you already know the workflow: pair the device, run the contraction, look at the trace. ForceIQ does the same thing, except the trace it shows you is annotated with onset and plateau, and the moment you end the set every clinical metric is computed and ready to read. There is no export step, no file shuffling, no CSV that needs to be auto-detected. The capture path is the lowest-friction way to get from setup to insight, and it produces the cleanest data because the sample rate is whatever the device actually streams, rather than whatever the export tool decided to write out.

This is what a first session looks like, end to end.

Pair your device

Open Capture from the sidebar. The device picker scans for supported force gauges in range and lists what it finds, so the picker itself is the current compatibility list. Click your device and the browser's BLE prompt confirms the connection. After that first pairing, the connection is held across page navigation, so you can move between Capture, IsoForge, and the dashboard without losing the link.

A few details worth knowing:

• Pairing is browser-level, not OS-level. You do not need to add the device in your system Bluetooth settings.
• Many gauges auto-shutoff after a period of inactivity, often around ten minutes. If that happens mid-clinic, just click the device again in the picker; the app reconnects without going through pairing again.
• Devices stream at different rates, and some stream slower than their published rate or change rate with a firmware update. You do not need to track this. The platform measures the rate from your actual recording and puts an RTD reliability badge on the metric tiles when the sample density does not support a confident slope. See sampling rate, RTD reliability, and what the badge actually means.

Set up the protocol

Pick the joint, the action, and the side. If you're running a bilateral assessment, pick how many trials per side. The patient's height (for moment-arm based torque conversion) and bodyweight (for mass normalization) come from their profile if you've entered them. You can still capture without these and the app falls back to force units cleanly.

You also pick the contraction intent for the set: MVIC, RTD or ballistic, or submaximal hold. The choice matters because it tells the analysis layer which metrics to surface. An RTD or ballistic set has no plateau, so the Control metrics are correctly hidden rather than reported as bad numbers. A submaximal hold set hides the Speed metrics for the same reason.

Capture the contraction

Hit start, cue the patient, and the live trace begins streaming at the device's native rate. The chart renders at 60 fps, which is fast enough that you can use it as biofeedback during the contraction itself, not just review it after the fact. Onset is detected continuously as the curve develops; the green onset marker appears as soon as the algorithm is confident, and the RTD windows and plateau band fill in from there.

End the set when the patient finishes. The full preprocessing and metric pipeline runs locally in the browser, which on any modern machine takes well under a second. The chart switches from live mode to the annotated review view you'll be looking at for the rest of the session.

Read the result

Six metrics, each tile led by a plain name with the technical name beneath it. Strength is the number most clinics already track. The other five are the ones the literature has been pointing at for a decade. Rate of force development is the one most worth knowing why you're measuring: explosive strength declines disproportionately faster than maximum strength during unloading and rehab, so the patient who looks recovered on peak can still be a step behind on speed (Ruggiero & Gruber 2024).

• Strength (peak force or peak torque). The most force the muscle produced. Still the headline strength measure.
• Explosiveness (RTD Early, 0 to 75 ms). How fast force rises in the first split second: rate of force development through the explosive, neurally driven phase. Often impaired before peak strength is, and often still impaired after peak strength has normalized.
• Build-up (RTD Late, 100 to 200 ms). How well force keeps building after the first burst: rate of force development through the developing-muscular phase. Read it alongside Explosiveness; concordance and discordance between the two tell different stories about the same contraction.
• Drift from peak (nRMSE). How far force sags from its best while holding, normalized to peak. Lower is better. Comparable across patients and unit systems.
• Steadiness (CV). How much force wavers during the hold, as the coefficient of variation across the plateau. Lower is steadier.
• Smoothness (Yank). How jerky the small changes in force are: the RMS of the time derivative of force during the plateau, amplitude normalized. Lower is smoother. Captures how abruptly force fluctuates, not just how much.

If the set was bilateral, the patient's dashboard shows their symmetry. Every patient starts in the simplified view, which leads with Strength LSI (peak symmetry on its own) and groups the six measures into Strength, Speed (Explosiveness and Build-up) and Control (Drift from peak, Steadiness and Smoothness). Switch the patient to the expanded view for the weighted LSI across all six, with the lowest individual metric surfaced beside it so a green overall does not hide a red component. Reading the dashboard covers both.

What if I have an existing file?

File upload still works. If you have a CSV from a previous session, or you're using a device that ForceIQ does not yet support over BLE, New Session → Upload runs the same pipeline against the file: parse, preprocess, detect onset, detect plateau, compute metrics, store. The output is indistinguishable from a captured session. The reason to prefer Capture when you can is friction and quality, not capability.

What to do next

• Fix a bad onset with a click. If the auto-detected onset is wrong, click on the chart at the actual start of the rise. Every downstream metric recomputes from the override. The auto-detected index is preserved on the session for audit; your override becomes the active value.
• Exclude rather than delete. If a trial is bad (countermovement at onset, slipped strap, fatigue), exclude it. The trial stays on the record for audit but does not roll into patient-level aggregates. Delete is for trials that should never have been on the patient in the first place (wrong patient, calibration run).
• Take the RTD reliability badge seriously. It sits on the Explosiveness and Build-up tiles. A low-confidence badge means the effective sample rate was below 60 Hz, so the 75 ms window held fewer than five samples. The value still ships; it just deserves less weight in the read.

End to end, a clean bilateral assessment takes about two minutes of capture and another minute of review. That is the workflow ForceIQ is built around.

References

• Ruggiero L, Gruber M. Neuromuscular mechanisms for the fast decline in rate of force development with muscle disuse, a narrative review. J Physiol. 2024. doi:10.1113/JP285667