RSI – Reactive Strength Index

COMMING SOON – JAN 2025

The reactive strength index (RSI) is a measure of an athlete’s ability to transition quickly from an eccentric muscle contraction to a concentric one. It’s a key indicator of athletic performance and is used to access an athlete’s reactive strength, which is important for sprinting, jumping, and changing direction.

There are two different ways to measure vertical jump using Dashr:

1. Vertical Rebound Jump for 5 Repetitions
2. Incremental Drop Jump

Vertical Rebound Jump for 5 Repetitions:

• For this drill you will need the Dashr|Jump Mat System. In the package you received there is a Jump Mat, Jump Mat Controller, USB battery, power cord, and charging brick.
• Install/open the Dashr app on your phone or tablet. (Create an account here if you have not already)
• Register your Jump Mat Controller in the app – Navigate to the “Device Registration” button at the bottom, power on the Jump Mat Controller and select it from the “Available” list and assign it a number. Write that number on your device. (This only has to be done the first time you use the device with this phone/tablet)

• Return to the home menu and select Reactive Strength Index.
• Connect the Jump Mat Controller to the Jump Mat if you have done so already.
• With the Jump Mat Controller on, press the “ID” button and select the number you assigned it (in registration) from the drop-down menu and press the “Connect” button. If it does not work the first time, repeat.
• Once all devices are connected, press the “Start Testing” button.
• Once in the drill you will notice “Jump Number” and “Initial Drop Height” towards the bottom of the screen. For the Vertical Rebound Jump that initial drop height needs to be 0 cm. As a result, the jump number will be 5 jumps.
• Check in the appropriate athlete (details here) – optional but STRONGLY suggested so you can electronically save the result to your account.
• Have the athlete step onto the mat and when they are ready, press the “SET” button.
• The athlete can now jump 5 times, landing on the mat each time. RSI is calculated by dividing flight time by ground contact time, so the goal is to maximize their time in the air while minimizing time on the ground.
• After 5 jump are recorded, a Max and Average RSI are reported. Given that the athlete starts on the ground, the first of the 5 jumps is ignored. The Max is the best RSI from last 4 jumps, the Average is the average RSI across the last 4 jumps.
• Check-in the next athlete and repeat!

Incremental Drop Jump:

• For this drill you will need the Dashr|Jump Mat System. In the package you received there is a Jump Mat, Jump Mat Controller, USB battery, power cord, and charging brick.
• Install/open the Dashr app on your phone or tablet. (Create an account here if you have not already)
• Register your Jump Mat Controller in the app – Navigate to the “Device Registration” button at the bottom, power on the Jump Mat Controller and select it from the “Available” list and assign it a number. Write that number on your device. (This only has to be done the first time you use the device with this phone/tablet)

• Return to the home menu and select Reactive Strength Index.
• Connect the Jump Mat Controller to the Jump Mat if you have done so already.
• With the Jump Mat Controller on, press the “ID” button and select the number you assigned it (in registration) from the drop-down menu and press the “Connect” button. If it does not work the first time, repeat.
• Once all devices are connected, press the “Start Testing” button.
• Once in the drill you will notice “Jump Number” and “Initial Drop Height” towards the bottom of the screen. For the Incremental Drop Jump, change that height to the height of your drop. As a result, the jump number will be 1 jump.
• Check in the appropriate athlete (details here) – optional but STRONGLY suggested so you can electronically save the result to your account.
• Have the athlete step onto the box and when they are ready, press the “SET” button.
• The athlete can now drop down onto the mat and perform a vertical jump, landing back on the mat.
• RSI is recorded!
• Check-in the next athlete and repeat.