Harley confirms that by stressing your body too much (e.g.) by overtraining), you can damage your metabolism & gain weight. So did I. But then it’s all about how you handle it: What you think you are you really are!!! Your self-talk is everything! So true! His tips in short: When you overtrained = unhealthy lifestyle, then admit you went wrong and just go back to a healthy lifestyle: no insane training, no high heart rate training, just light movement – chill. Enjoy.