SelfSyncRecord message
Record messages are the time series of an activity: the device writes one every second (or using smart recording, when something changes), with everything it measures at that moment: GPS position, altitude, heart rate, speed, cadence, power, temperature and so on. They are by far the most numerous messages in an activity file and the source of every chart and map.
Fields
Moment the values were measured, in UTC.
Latitude. FIT stores coordinates as semicircles: multiply by 180 / 2^31 to get degrees.
Longitude. FIT stores coordinates as semicircles: multiply by 180 / 2^31 to get degrees.
altitudeFloat64Altitude.
Heart rate.
Cadence: revolutions per minute for cycling, steps per minute for running.
Distance covered since the start of the activity.
speedFloat64Speed.
Power output.
compressedSpeedDistanceByte[]Speed and distance packed together in a compact format, decoded into speed and distance.
Current slope.
resistanceUint8Resistance of the fitness equipment, from 0 (none) to 254 (maximum).
Time ahead of (negative) or behind (positive) the course or virtual partner.
Distance covered per cycle (pedal revolution, stroke…).
Ambient temperature measured by the device.
Speeds at 1 second intervals, the timestamp being the one of the last element.
cyclesUint8Number of cycles since the previous record, rolling over.
Total number of cycles since the start of the activity.
Running total of the power, in a compact format that rolls over.
Running total of the power since the start, used to compute averages.
leftRightBalanceEnumPower contribution of the right leg, when the right bit is set, as a percentage of the total. The left leg makes up the rest.
2 possible values
rightmask
Estimated accuracy of the GPS position.
Vertical speed.
Energy expenditure.
Vertical oscillation: how much the torso moves up and down.
Ground contact time, as a percentage of the step duration.
Ground contact time of the step.
activityTypeEnumBroad type of activity (running, cycling, swimming, walking, fitness equipment…) the data relates to.
10 possible values
allrunningtransitiongenericcyclingfitnessEquipmentswimmingwalkingsedentarywheelchairPushing
Torque effectiveness of the left leg.
Torque effectiveness of the right leg.
Pedal smoothness of the left leg.
Pedal smoothness of the right leg.
Pedal smoothness of both legs combined, for single-sided power meters.
Time with a 1/128 second resolution.
strokeTypeEnumType of stroke, for racket sports: serve, forehand, backhand, smash…
6 possible values
othernoEventserveforehandbackhandsmash
zoneUint8Zone of the court or table the ball was hit to.
Ball speed, for racket sports.
Cadence with its fractional part, kept for backwards compatibility.
Fractional part of the cadence, to add to it for a more precise value.
Total hemoglobin concentration in the muscle.
Minimum total hemoglobin concentration since the previous record.
Maximum total hemoglobin concentration since the previous record.
Muscle oxygen saturation (SmO2).
Minimum muscle oxygen saturation since the previous record.
Maximum muscle oxygen saturation since the previous record.
deviceIndexEnumIndex of the device that produced the data, matching the deviceIndex of a device_info message. The value creator designates the recording device itself.
1 possible value
creator
Platform center offset of the left foot.
Platform center offset of the right foot.
Start and end angles of the left pedal stroke portion producing positive power.
Start and end angles of the left pedal stroke portion producing peak power.
Start and end angles of the right pedal stroke portion producing positive power.
Start and end angles of the right pedal stroke portion producing peak power.
Speed, with a larger range than the speed field. Prefer it when present.
Altitude, with a larger range than the altitude field. Prefer it when present.
State of charge of the light electric vehicle (e-bike) battery.
Motor power of the light electric vehicle (e-bike).
Vertical oscillation divided by step length.
Ground contact time balance between left and right foot.
Step length.
Distance covered per cycle, with a larger range for paddle sports.
Absolute pressure measured by the dive computer, atmospheric pressure included.
Current depth. 0 when above water.
Depth of the next decompression stop.
Duration of the next decompression stop.
Time needed to reach the surface, decompression stops included.
No decompression limit: time left at the current depth before a decompression stop becomes mandatory.
Central nervous system oxygen toxicity (CNS%).
Nitrogen tissue loading.
respirationRateUint8Respiration rate, in breaths per minute.
Respiration rate, in breaths per minute.
gritFloat32Current grit score: how difficult the trail is.
flowFloat32Current flow score: how smoothly the rider keeps their momentum.
currentStressFloat64Current stress level.
Estimated range left with the e-bike battery.
Battery level of the e-bike.
Assistance mode of the e-bike, whose values depend on the system.
Assistance level of the e-bike motor.
Estimated time left before the tank runs out of breathable gas.
Surface air consumption based on tank pressure.
Surface air consumption based on gas volume.
Respiratory minute volume: volume of gas breathed per minute.
Current ascent rate.
Current partial pressure of oxygen.
Core body temperature, from a core temperature sensor.
mesgNumStringGlobal message number identifying the kind of message. Decoders use it to know which profile to apply to the data.