For today’s edition of Dear Mark , I’m answering three questions about training. First, why might cycling feel harder than running at the same HR, and what should be done about it? Second, is it safe or smart for a footballer to try to become a fat-burning beast when he’s currently in-season? And finally, what do I think about the relatively new Orange Theory gyms? Are they good, bad, or both? Let’s go: Hi Mark, I was wondering if you could answer this (or maybe answer in a blog post). I got a copy of primal endurance a couple of months ago and love it, great book. I’ve been running using Dr Maffetone 180 formula for a fair while (with good results whilst running), I also use the formula whilst hiking on trails and using gym equipment like the eliptical trainer. However I used to do a lot of cycling years ago and recently bought a bike as a different form of training for days when I don’t want to run/hike or use the gym. However when I use the 180 for cycling it feels A LOT more