You have to go heavy with calves. Go slow when going down into the stretch portion of a calf raise and hold it for a second and then back up in a powerful motion. I am not a big believer in high reps for calves because calves are used to high rep activity. You use them every time you take a step. Also, the stretch is important to get the full range of calf motion. I see a lot of people who do calf raises way too fast They almost bounce. You aren’t going to get any calf development doing that.