Monitoring Squats

Hi everyone,

I'm new to Arduino as I recently picked up a starter kit with hopes to build something simple and interesting that I could learn from and move my way up into intermediate level with the passage of time. I have an automotive background with very well understanding of electrical flow, hopefully this will ease my learning phase.

Specifically, what i'm hoping to build for a school project is a device that could signal as I performed a squat exercise. In this case, I was thinking about using a 3 axis accelerometer to input to my Arduino UNO when it senses a change in motion. Leading to the Arduino turning a green LED on when I make my way down to squat and turn a red LED on as I make my way up.

So that would be green during the "initial phase" and red during the "recovery phase"

Here is a picture of the movement along with where I believe would be ideal to mount the boards.

I was hoping to get some advice from you guys with what sensor that I should stick to, I was thinking about using a ADXL335 - 5V .. What do you guys think? any advice would be highly appreciated.

thanks in advance!