US 6,898,550 · Granted 2005-05-24
The Patent That Taught Your Phone to Know You're Running Uphill
This patent describes how a wearable device or app can figure out whether you're walking or running uphill by measuring your heart rate, breathing, and other body signals — without needing GPS or a fancy incline sensor. It's like giving your fitness tracker a sixth sense for terrain.
The plain-English version
What it protects
The claim covers a method for determining whether a surface has a slope (like a hill) and measuring how steep it is, using only physiological measurements from the user's body — such as heart rate or oxygen consumption — rather than relying on external sensors or map data. What's protected here is the specific technique of inferring terrain grade from internal body signals during walking or running.
Why it matters
This patent, filed in 2000 and granted in 2005, sits at the intersection of wearable fitness technology and biomechanics. By using physiological data to deduce terrain, it enabled fitness trackers to provide smarter training insights without bulky external hardware. This approach became foundational for modern fitness watches and running apps that adapt coaching feedback based on whether you're climbing or descending, making workouts more personalized and realistic.
Real-world use
When your fitness watch tells you your effort level changed dramatically during a morning run, it's likely detecting that you've entered hilly terrain by reading shifts in your heart rate and breathing — exactly the kind of inference this patent locks down.
Original USPTO abstract
In one embodiment, a method involves determining at least one calculated parameter based upon at least one determined performance parameter of the user and at least one determined variable physiological parameter of the user. In another embodiment, a method involves identifying at least one of an existence of a non-zero grade of a surface and a value of the grade of the surface based upon at least one determined variable physiological parameter of a user.
Patent details
- Publication number
- US 6,898,550
- Filing date
- 2000-08-21
- Grant date
- 2005-05-24
- Assignee
- Fitsense Technology, Inc.
- Inventor(s)
- BLACKADAR THOMAS P., DARLEY JESSE
- CPC class
- G01C22/006
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