Great question Bill. It would be great to use the machines, as long as you aren’t tiring yourself out with additional exertion. And you can also go longer, at least during these early cycles. Many athletes won’t reach Zone 1 heart rates walking on flat or gentle terrain and will need to be hiking rolling hills or steeper terrain. Running works for some, but walking on an inclined treadmill might be a good choice for you. Walking is less stressful and more economical than running, so it’s ok to do more of it in a training program.
This session puts an emphasis on both Zone 1 and Recovery. Both are important.
One intent of this session is adding to your weekly training volume:
Aerobic adaptations are more likely to occur with higher volumes of training. There is a limit to how much Zone 2 training that can be done in a week. By doing some Zone 2 and some Zone 1 training, athletes can tolerate a higher volume of training than Zone 2 alone. *Modulation* of training sessions is a normal strategy used by successful endurance athletes, but each athlete will have a different allocation of Zone 1 and Zone 2 training. If you are trying to get additional training volume to improve aerobic function, it makes sense to get your HR up into or very near the target range.
Another intent of this session is Recovery:
In this program, we’ll look at recovery in different time scales: monthly, weekly, and daily. This session you’re referencing is emphasizing recovery on a weekly basis – some athletes will eventually emphasize this recovery effect more than Zone 1 training volume. Using these sessions for recovery will deliver oxygenated blood to sore muscles, flush away negative by-products, and overall help your muscles recover and rebuild stronger. Working out too hard on a “recovery” session can reduce or eliminate these benefits. You are trying to feel better at the end of one of these session, not feel more tired. During our hardest weeks of training, recovery sessions might not be running or even hilly walking for some athletes, but could be cycling, rowing, or swimming so that you are getting off of your feet.
We’ll label these sessions Zone 1 / Recovery because each athlete could have a different preference on how they use these sessions.
It’s important for everyone to pay attention to their responses to weekly training volume and the effect that these Zone 1 / Recovery Sessions have on their ability to train at that volume.