Spinervals Competition 4.0: Muscle Breakdown continues the excellent track record of the Spinervals series of exercise programs for cyclists. Designed for use indoors with a stationary trainer or exercise bike, Muscle Breakdown is a challenging workout for serious athletes, whether competitive bicycle racers, triathletes, athletes in another sport looking for cross-training, or simply dedicated recreational riders who want to improve their strength and fitness.

Muscle Breakdown runs 49 minutes, and is rated 8.5/10 on the Spinervals difficulty scale, indicating that it's less intense than workouts like Suffer-O-Rama or Time Trial Special, but that's only true in terms of the cardiovascular part of the workout. By the end of the workout, your leg muscles will certainly be informing you that the workout was quite intense indeed. Let's take a look at the workout in detail:

The opening warm-up of easy spinning followed by three sets of 30 seconds on/30 seconds off full-out efforts is a familiar start for Spinervals participants. The high-cadence superspins in the next set are also familiar but quite welcome, especially for riders like me who tend to ride a too-low cadence and need the practice of spinning. (And Coach Troy Jacobson is a great one to motivate you to spin! spin! spin!)

The two "acceleration sets" are where Muscle Breakdown really gets interesting. The first of these is a full five minutes of alternating 4-second segments of all-out effort and easy spinning, and the second is three minutes of the same exercise. That's right, just 4 seconds of effort: as the name of the drill says, this is a fantastic way to work on exploding forward on the bike. This is exactly the kind of exercise that's impossible to do out on the road, and it really makes Muscle Breakdown earn its place in your indoor training program.

Your legs will probably be fried after the first acceleration set, so you do get a two-minute rest... but after that, Coach Troy tells you to get off the bike. What? Yes, that's right: the "isometric squats" set is done off the bike. They're excellent for building muscle, and they're deceptively simple looking: your legs will be burning by the time you're done, and you'll be glad to hop back on the bike and spin.

The one thing I'd wish for here is a clearer explanation of the intended purpose of this workout: it's focusing on the leg muscles, sure, but I'd have appreciated a bit mo†R%f an introduction explaining in more detail what the workout was for. Judging from the exercises, I'd say a mix of explosive speed and steady-state power, but I'd like to hear that from Coach Troy, along with some tips on how Muscle Breakdown might be used in an overall training program.

All in all, Muscle Breakdown is a varied and interesting program that offers a very different type of workout from the other Spinervals programs; it's well worth adding to your indoor training workout library. It's tough but also quite focused, and as always Coach Troy does an excellent job of providing encouragement and pacing throughout the program.

The DVD

Video

Spinervals Competition 4.0: Muscle Breakdown looks perfectly fine for what it is: an exercise program. The image is a bit soft, but it's bright and clean, and pleasant to look at. The graphic aids (the perceived effort bar, the countdown of time left in the program, and the suggested gear ratio) are clear and easy to read. It's presented in its correct 1.33:1 aspect ratio.

Audio

The soundtrack for Muscle Breakdown is solid, allowing you to concentrate on doing the exercises at full effort: Coach Troy's voice is always clear and easy to understand, and the music soundtrack is correctly balanced, fading off when Coach Troy speaks and rising up when it's time to buckle down and get to work. The music is well done and provides a useful guide to the tempo of the exercise, whether it's an easy spin or a tough all-out effort.

Extras

There are no special features here, but as I've commented on other Spinervals DVDs, the menu design and chapters are well-thought-out. Each segment of the workout has its own chapter, making it easy to skip ahead or repeat segments as desired, and the menu clearly lays out the whole program.

Final thoughts

If you want to improve your leg strength and acceleration on the bicycle, Muscle Breakdown offers a great workout for your leg muscles to get you on the right track. Even if you're not primarily a competitive cyclist, if you want to work on leg power, this is a great way to do it; I can see that this will be an excellent cross-training program for my fencing, for instance. Muscle Breakdown is quite different from any of the other Spinervals programs so far, making it an excellent addition to your collection of indoor training workouts, alongside Suffer-O-Rama for interval training, Time Trial Special for steady-state effort, and Sweating Buckets for aerobic fitness and recovery. Highly recommended.