NASH consists of 2 parts that you should complete one after another. Between part a) and part b) as well as b) and c) you have 2 minutes rest.
This is how NASH works:
You'll need a stopwatch. Every 60 seconds you perform 15 Wall Balls as quick as possible. Repeat this 10 times, every minute on the minute until 10 minutes (EMOM 10) have passed.
Example: If it takes you 30 seconds to complete 15 Wall Balls, you have the remaining 30 seconds to rest until next minutes starts.
Part b) and c) follow the same pattern.
Scaling: You can scale NASH by reducing the repetitions and therefore extending your rest times