This one is deceptively difficult. Both the wall balls and assault bike leave you breathing heavy and holding the sandbag against your chest while trying to recover your breath is no fun 😈. 

Carried the sandbag from the garage door to mailbox for each 50-foot section. I held at least 65 RPMs on the bike so that I could finish the 15 calories in a minute,  As written, this is done with a heavier wall ball (30/20), but I used what I have at home (14).