The allure of the current set of exercise apps is that the device automatically tracks the effort, using existing features like accelerometer and GPS, and there's no input required. FitBit tracks steps, some apps use GPS to track distance covered and derive stats. It's nearly literally a no-brainer to use them, and they require no cumbersome gear to wear. Even a heart rate monitor is small and unobtrusive now.
Unfortunately for lifting and many other forms of exercise, the apparatus is not built into the device you already have or can strap on your belt and forget about. In addition to needing special-purpose measuring equipment, the user would have to incorporate the device into the exercise.
A barbell could know it's been picked up and put down, but how would it know how much weight is on it? RFID in the plates? A tennis racket or baseball bat could track swings and speed, but would anyone even care for that metric?
Buying an RFID weight set or a piece of equipment with more sensors on it, or attaching a phone to a bat are all very signifiant barriers of entry.
FitBit, Wear, Microsoft Band, iWatch aren't getting a ton of adoption for these simple metrics, how do you sell the others? Ie 80% of Americans have smart phones, 10% will invest in wear devices, maybe it's just .1% that will invest in bat technology.
Unfortunately for lifting and many other forms of exercise, the apparatus is not built into the device you already have or can strap on your belt and forget about. In addition to needing special-purpose measuring equipment, the user would have to incorporate the device into the exercise.
A barbell could know it's been picked up and put down, but how would it know how much weight is on it? RFID in the plates? A tennis racket or baseball bat could track swings and speed, but would anyone even care for that metric?