When I initially went to Orange Theory, I was pretty sure I wouldn't like it.  My friends' descriptions of it made it seem so amped up, so stressful, so opposite to what I'd been practicing for 20 years in my main exercise, yoga.

I remain totally surprised by how much I love it. It turns out that I not only find it fun and rewarding, I also find it to be compatible with yoga, even supportive of it.

I like Orange Theory for several reasons. I appreciate the interval approach, I love the heart rate monitors you use to observe your body's aerobic data during the class, and I respond well to the instructors, playlists, and overall supportive vibe. Orange Theory motivates me to improve my cardiovascular system and BMI, and I see results from pushing myself in ways I wouldn't otherwise.

Science, of course, shows that working out regularly takes care of a bunch of bodily ills. So all in all, as I wrestle with the calorie-burning-slow-down in my 40s, I have benefited hugely from Orange Theory (Here's their take on the science).

When I started practicing yoga regularly in my early 20s, I was a runner. I enjoyed feeling strong generally, and mentally I cherished that post-run clarity. The cortisol feeling was addictive, and I found myself hazy and downcast after a couple of days' break. Running was good for my runaway brain: It was a rote set of actions, a never-ending series of routes through New York City and London, where I lived, and it felt like escape. I relied on it to keep me feeling connected and happy.

Yoga came at me so differently. After I took my first full yoga class I felt clear-headed, stronger, and stretched. My lungs felt different, bigger, or longer, somehow. Most of all, I walked home feeling so peaceful -- we had spent five minutes at the end lying on the ground with our eyes closed, doing nothing (in savasana or corpse pose). The whole experience stuck with me and ultimately pushed me to become a teacher, yoga studio owner, and trainer of teachers.

A yoga class doesn't have a lot in common with an Orange Theory session, but the two events do share a group sense of purpose, a teacher, and the desire to self-improve. (They are also both expensive). Whereas Orange Theory challenges the physical body, yoga challenges the physical body and then some. It goes on to challenge the mental and emotional layers of the body as well.

This is what makes yoga so much more difficult than interval or circuit training, or frankly than any straight-up form of exercise. It's also what makes it so rewarding. Linking your breath with time-tested positions for the arms, legs, and trunk, and holding such inversions as headstand 1 or shoulderstand 1, absorbs you in a way that heightens your awareness of how your body and environment exist together, ideally to include some harmony. In pushing yourself beyond what you believe to be your limits -- we attend group classes in order to safely take risks among peers and be guided by a knowledgeable teacher -- you develop a sharper sense of what you're capable of. And then, in resting at the end of the class, in corpse pose, you allow the body to fall into a more relaxed state.

It's both of these things, the sharper awareness and the relaxed state, that keeps people coming back to yoga regardless of what other exercise they are doing.

A well-taught yoga class, one that includes correct alignment information, is not only deeply absorbing and relaxing. It is thoroughly strengthening for the body's muscles and joints. Yoga is a practice that anyone of any age can do, and it's something that becomes even more important as you get older and your body changes its relationship to gravity. 

Despite the the science that lies behind it, and including its real benefits, Orange Theory's workout should never replace and a thousands-year-old philosophical science, yoga. At best, the two practices should should coexist. At worst, yoga will stay while Orange Theory fades. While Orange Theory is the perfect modern workout -- it's 55 minutes of cardio plus strength; you get instant feedback and not one minute of silence -- it can't teach equanimity. 

This is the most important thing that yoga teaches: steadiness and ease in the face of change. The postures, many of them very challenging, are just the first step on your path of working toward relaxed awareness. You develop this awareness by pushing yourself, relaxing yourself, and then by letting all of it go. It's the letting go -- from action to stillness -- that provides some of life's deepest lessons, and practicing this over and over in a yoga class increases your chances of doing it in your daily life. This, in turn, helps you be steadier and more easeful as things around, as you, inevitably change.

The bottom line, I suppose, is that I wish Orange Theory had savasana! :)