The Key to Endurance Fitness

By Shaun Wadham, Level One Triathlon Coach, Registered Fitness Leader

There are many factors that will influence our overall fitness and hence our performances when racing. Speed work, rest, eating correctly, tapering and mental preparation are just some of them. The biggest physical factor though is the aerobic fitness base you build in the months before you plan to compete in an event.

Endurance events such as triathlons or runs over about 3km require us to take most of the required energy from our aerobic (in the presence of oxygen) energy system.  It is therefore logical and crucial that we train our aerobic energy system so that its capacities are well developed.  A big aerobic engine is the key to being a good endurance athlete.

The catch though is that most people do not have the patience to build a base correctly. The reason is that for the first 12 weeks or so of your training program, you will have to put on a heart rate monitor, train almost exclusively at 65-75% of your maximum heart rate and put your ego aside. The higher heart rates are anaerobic (lactic acid producing) and you shouldn¹t exercise at them until your base has been built. The reason is that the improvement you can get in performance from developing your aerobic energy system is huge compared to the improvement in performance you can get from doing the high-end anaerobic (lactic acid producing) workouts.  Training too hard, especially in the base phase may actually result in a decrease in aerobic fitness. From my experience it is also the single most cause of injury amongst people training for an event. Further our bodies cannot develop both systems very well at the same time. All this means that to build a base properly, an athlete has to have the patience to work the aerobic system exclusively for a huge block of time.

Your perceived effort can be quite low while you are training in the aerobic zone. What you should be experiencing is some discomfort but you should be able to hold a conversation with your training partner. Training sessions will feel the opposite of the “no pain no gain” mentality that says training should be painful and muscles need to burn to get benefit. This is definitely the case if you have a good base fitness and are coming up to an event you have been training for but right now, this is absolutely not correct. By training in the aerobic zone for the first 12 weeks or so you will be getting a huge benefit that will show up months down the road.

Mark Allen, a legend of the Hawaiian Ironman Triathlon stated that when he started back each season after a break, he had always lost a lot of his aerobic capacity. During his first few months of training, he would literally have to walk up even the easy hills on his runs to keep his heart rate from going too high and kicking his body into anaerobic metabolism. Slowly, over those next 12 weeks though his aerobic energy system would improve and the pace he would run at whilst keeping his heart rate in the aerobic zone would increase significantly.

So if you have had a long break it is important to be disciplined and follow the base training guidelines mentioned above.  This means that every session is pretty much the same as far as intensity goes. This may mean that you have to walk up some hills but if a world champion like Mark Allen can bring himself to do it so can you.  Once your base has been built you will have plenty of opportunity to work in the more “painful” training zones.