Is the allocation where each athlete trains 30 hours per week a Nash equilibrium?

Is the allocation where each athlete trains 30 hours per week a Nash equilibrium? (Hint: you can check to see if the payoff rises when, say, Ameer increases to 31 and then when he reduces to 29. You don't have to check for Christian's incentives because the situation is symmetric). (Let's use the Tullock model to describe their behavior. For each athlete winning is worth 120 hours per week)