Long, Slow Distance (LSD): It will only take you so far

Wanting to become an endurance athlete? Wanting to become a better endurance athlete? There is still a widely practiced belief that the best way to build and improve endurance are to just go out there and do it- long and slow, then a little longer and slow, then maybe even longer and perhaps a little slower.  This is true for people starting a journey on running anything from a 10k to a marathon, cycling events, and triathlon.  The problem is that learning to build endurance and learning to improve endurance are two very different things.

In order to explain this you must first understand a few basic concepts in building fitness.  In the early 1900s a Hungarian endocrinolgist Hans Selye developed the concept of General Adaptation Syndrome (GAS).  While originally determined in stresses such as disease, the syndrome has also been proven to relate to training and fitness. After all, exercise/training IS a stress on the body.  Seyle basically said that when exposed to stress an organism creates a short-term response to deal with the stress, and then a long-term adaptation to the stress, should the organism live through the initial stress. Essentially, “What doesn’t kill you makes you stronger.”

The explanation of GAS as it relates to exercise is simply explained as follows:

Our bodies like to remain in a normal biological functioning state known as homeostasis.  This is where we function the best, and our organ systems are constantly monitoring our internal and external environments and adjust their functioning to maintain homeostasis.  From a fitness standpoint, this is our normal working capacity.

The second phase of GAS refers to the body being exposed to a stress (exercise) that sets off an alarm. This alarm creates a cascade of events that disrupt homeostasis and actually reduce normal working capacity.  The catch in this phase is important: in order to set off the alarm the magnitude of the stress MUST be greater than levels previously experienced.  If it is not, then the alarm phase is not reached.

The third phase is resistance.  In this stage, once the stress has been removed (recovery) the body works rapidly to return itself to homeostasis.  In doing so, however, the body actually creates an INCREASED work capacity, thus making us stronger.

So, what’s the take home message here?  In newer or untrained athletes, just increasing your distance each training period IS enough to set off the alarm- because you’ve never done it before. But once we have adapted to certain distances, just going the distance alone will not set off the alarm, and therefore no improvement in fitness will occur.  In these instances increases in intensity must be introduced in order to set off the alarm and improve performance.  And, in fact, these intensities need to be extremely intense.  Very high intensity exercise works the lactate threshold and VO2 max systems of the body which allow you to sustain harder efforts longer. In other words, allow you to kick your endurance speed up a notch (or two, or three).

So, is there any place for long and slow distance? Yes.  In this type of training we can completely deplete our glycogen stores and teach the body to tap into fat stores more efficiently.  Using all of your stored sugar is most certainly a homeostatic stress, and thus sets off an alarm. However, only if the depletion is greater than ever before.  Ultimately this type of training can assist in teaching your body to better use fuel- and thus help you to go longer.  But does nothing to improve VO2 Max, which allows you to go faster.  Therefore, in order to go longer and faster, you need to do both. How to get there is another topic all together and I will write more on this later…

Comments are closed.