Training zones

Janes:

This is a great question with a not very great answer. Training intensity zones are already a somewhat artificial construct. The less tied they are to your personal metabolic response to exercise, the more artificial, arbitrary or disconnected from reality they are. The percentage of some HR value, especially maxHR and even more especially if that maxHR is determined by an age related formula is the most arbitrary and thus suspect method of setting zones. We debated long and hard before including it our book. I won’t get into the thought process here.

Being able to anchor the zones to some actual metabolic events in your physiology is the first step in making the zone system meaningful to you personally.

WARNING: Keep in mind that the HRs at which these events occur are not fixed and will vary form day to day depending on your recovery status/level of fatigue as well as fitness. So trying to define these zones down to a beat or two of HR is false precision.

Having 2 anchor points, AeT and AnT gives you the top of Zone 2 and the top of Zone 3 in a convention 4 or 5 zone system. The difference between aerobic zones (1 and 2) is a bot arbitrary and not easy to define. The distinction depends a great deal on the aerobic fitness of the individual. A safe rule of thumb for setting Z1 limit is 15% below Z2 upper limit.

The upper intensity zone 4 is going to be set by an intensity you can maintain for 5-8 minutes at the most. This is hard training that is why it is done in interval style. If you use Z5 then this is as hard as you can go for about 1-2 minutes.

I hope this helps,
Scott

Janes;

When speaking about athletes with a very high aerobic capacity as measured by AeT speed have special needs that greatly influence their choice of training intensity.

I will try to explain here:
Lets’s use a marathon runner as an example because we can speak about some specific numbers that will help illustrate several points. The marathon event is competed at an individual’s aerobic threshold; roughly 2mMol/L of blood lactate concentration which typically corresponds to the top of Z2 in most zone systems.

For an elite (sub 2:10) male marathoner this means a pace of faster than 5 minutes/mile (around 3:10/km). Running at this pace places large loads on the neuromuscular system even though the metabolic stress is only moderate because it is the aerobic metabolism producing 90% of the energy.

If this elite runner trained frequently at his Z2 (AeT) limit he would not recovery between workouts and his motor nervous system would quickly become over trained. So he needs to do MUCH more of his aerobic training in Z1 as what would be called Aerobic Restoration Work not as Aerobic Capacity Building work. His aerobic capacity is not his endurance performance limitation as it is for most recreational runners.

Now consider a recreational marathoner hoping to break 4 hours. That running pace does not place so much neuromuscular load because it is so slow. These runners are very much limited by their aerobic capacity (metabolic) and for them, training near the AeT will yield a much bigger and better aerobic training effect.

I discovered this phenomenon first have when training elite XC skiers. We discovered that 1 hour or so of Z2/week (in a 20 hour training week) was about all they could handle without undue fatigue. They of course were also doing Z3 and Z4 and strength training in these weeks. Where as my younger junior XC skiers could do virtually all their aerobic training right up near AeT (Z2 top) because the neuromuscular loads were relatively much lower.

We see the exact same thing with many of the people that come to us for training and coaching. Most are aerobically deficient and NEED to train near AeT to increase aerobic capacity as their primary training emphasis.

Looking at what elites do for training is very interesting and it can help inform what you might want to do. But blindly copying what elites do is why we have so much misinformation about the use of high intensity training all over the internet.

This is why we spent so much time in our book explaining how the aerobic system supports all endurance efforts and why basic aerobic capacity is so important.

I have provided the simple 10% rule elsewhere in these forums as a way to determine when you need to consider using more Z1 and more Z4 training.

Scott