Efficiency is defined as the use of oxygen per energy output – for runners (cyclists, swimmers, etc.) it is oxygen use over the distance traversed in a given period (pace). Efficiency is gained through neuromuscular coordination. Better neuromuscular coordination leads to less wasted motion. Less wasted motion leads to less energy wasted. Reducing energy costs reduce oxygen costs.
Anyone who begins a new workout program will initially gain in conditioning and become more efficient in that activity just by doing the activity. This will always be the case in going from couch potato to athlete. It is also true (but perhaps less dramatic) in sports cross-overs (i.e. cycling to running). In those early workouts, training the muscles to respond correctly to the specific requried movements happens through doing more of that activity until the neuromusclular system “knows” the movements. This is when we become more coordinated in the activity. Whether that activity is on an elliptical trainer, swimming or running (or any other sports) the process is the same. Early gains are recognized through slower, repetitive efforts and gradually increasing your bouts of exercise.
Here is the point at which the “more is better” philosophy diverges from what science has shown to benefit you best in becoming efficient. Once you gain basic movement coordination, aerobic conditioning and muscular strengthening becoming more efficient depends on doing something different – not more of the same.
It has been definitively shown that becoming an efficient runner first and foremost comes through high quality running.
A key element in becoming efficient is to reduce your foot contact time. This is not done by artificially trying to run on your forefoot and stay off the ground during your runs. Foot contact time is reduced through high speed training & drills. By becoming stronger at faster movements, your body learns to coordinate it’s muscles better and reduce excess movements. You end up staying on the ground less time. You end up faster.
Secondly, efficiency is race pace specific. You do not get efficient at your marathon 8:00/mile pace by running at 9:00/mile on long runs and then adding in some speed work on the track at 7:00/mile pace. This is not an averaging thing! You must run progressively more and more miles at your goal pace (8:00/mile) in order to become efficient at that pace! You do not become successful at any race distance (not the mile and not the marathon and not anything in between) without running many miles at your projected goal pace.
The final point of course which science is reasonably clear is the crossover point at which “what you do” with the miles is more important than “the number miles”.
Quite surprisingly to many of you, it is no more than a modest 40 miles a week (or less depending on the study)! At this point there is little doubt that what you do with your miles is more important than adding more miles. One study showed better progress in race times for a group averaging 38 miles per week over 50 mile a week runners! (They all started at 38 miles per week. One group stayed at 38 but changed some miles to high quality running and the other group just added more miles to 50.) Think about it, 31% more miles did not get better results!
Guess what, we also know that once a runner has the ability to run 20 miles per week they will make great gains by changing the nature of what they do from – just running to incorporating speed work and drills. They will progress far faster than the 20-mile-a-weeker who adds more miles versus adding more of the right miles. Anecdotally, I have found far greater progress introducing “speed” work even to complete novices than making them jog continuously until getting up to 20 miles a week. The nature of “speed” of course is relative to the individual.
I have one final application to share. Regarding Olympic/elite level runners does this still hold true? The answer is an undebatable, yes – just on a higher scale. There has been analyses done on Olympic marathoners’ training. After evaluating scads of data guess what single element most predictive of their performance? It was the average pace of training: the faster the paces in training, the faster they ran in the marathon. Training mileage was not well correlated. And the highly touted “miles” that Kenyans run is inaccurately portrayed. They run a higher percentage (about 30%) of their miles at 10k pace or faster than other runners. (Do the math. Even at 80 miles per week they would run the equivalent of race four 10Ks per week as part of their training!) They only run high mileage for a few weeks when they run as a team, once a year. The rest of the year it is far more modest. It is true that they run far more than the average age group runner. They look for every tenth of a second difference – it may mean the difference between Gold and nothing. The point is that even at this level, they become more efficient (as well as the fastest) through a higher percentage of high speed workouts to gain power and efficiency in their movements.
There is no doubt that adding many more miles will result in some improvement – along with a huge increase in chances for injuries. The real question to a competitive athlete is this: do you want to put more time than you have to into your sport to get the results you want?