Cardio and catabolism

I hear a lot about excess cardio being a great way to lose hard earned muscle and not just fat. Is this true for all muscle, or just the areas involved in the cardio (assuming adequate calories). The reason I ask is that I’m about to start training for a mountain biking holiday in May. This will involve 1 hour intensive per morning 5 days per week, and 3-4 hours per day at weekends (no days off). I will still be in the gym 4 evenings a week, though legs day might have to evolve a bit :o| The holiday itself will be around 6 hours per day for 7 days. Obviously this will be almost all leg pushes, and I’d hate to think that I’d go all pigeon chested by summer after all the work it took to build upper body since the last time I did this kind of biking (2 years ago before - before I joined a gym). I’m thinking of using massive doses of Surge in my camelback for energy, but am also wondering if Mag-10 might be a good muscle preserver in this kind of situation. Also I’m thinking that Mag-10 would be a great way to lessen the extreme pain and strength loss I always got after the first day or 2 of the holiday, but I’m not sure about Customs at the airport (flying from UK to Spain). Any thoughts would be appreciated. Paul

I took 6 bottles of MAG-10, along with a slew of other Biotest goodies through customs in Germany and then through in Greece (although Greece is a bit more lenient than most). Not sure about Spain, but I would suspect that if you have them in your carry-on, then it is more likely that you might be questioned domestically than abroad.