Yeah, 40/30/30 is a good start to see what works for you. I love my keto diets, but for a beginner who hasn't adapted to them, they may interfear with his ability to train intensly, but he could try a ckd and see if he can hack it. With the 40/30/30 he'll have a good balance, and it doesn't take a great deal of discipline to follow. He can adjust and experiment from there to find what gives him the best results.