In this episode of MASS Office Hours, Dr. Eric Trexler and Dr. Mike Zourdos answer questions submitted by listeners and viewers in the live chat. Topics include response variation, individualizing training, movement screens, rest days, protein intake recommendations and consistency across the week, the interference effect, exercise variation and joint pain, muscle and strength loss during deloads, volume cycling and “resensitization,” the effects of alcohol on metabolism and body composition, the pros and cons of caffeine, and much more. The MASS crew goes live for Office Hours every Wednesday night at 7pm eastern time. Be sure to join us for a future episode! If you'd like to submit a question ahead of time, please use this link: https://forms.gle/9Ah39mefs8cuVa9H7 Time stamps: 0:00 Introduction 6:32 Response variation and individualizing training prescriptions. 27:36 Using movement screens to assess capability or injury risk 34:23 Doing a little bit of exercise on a “rest” day 39:10 Protein intake recommendations and consistency across the week. 51:23 Rucking and the interference effect 57:37 Exercise variation and joint pain 1:07:06 Muscle and strength loss during deloads 1:12:25 Volume cycling and “resensitization” 1:22:31 Effects of alcohol on metabolism and body composition. 1:27:42 Recommendations from Eric’s bookshelf 1:30:49 The pros and cons of caffeine