This schedule is no different than my schedule from 30 years ago and I don't consider it problematic at all. You frame it as 15+ hour days by including all aspects of their day as "work" but no normal adult includes their workout time and their social engagements as part of their work day. Time spent in sports is fun, not work. If it is work, then quit. Time spent in gym class and lunch is not work. Remove all that bloat from your framing and it is a very reasonable workload.