Anatomy of the 400 m run

The 400 m run is one of two mandatory events in the speed portion of the Speed Strength Combine.  A breakdown of how this event should be run and what it really tests follows.  Also, an exploration of what is considered "good" is undertaken.

First of all, a little science behind the physiology of running a 400 m sprint.  This event tests speed, power, strength, flexibility, but also depending on how long it takes a runner to travel 400 meters, the anaerobic and aerobic capacities are tested as well.

Recent research looking at aerobic versus anaerobic energy systems in trained athletes found that in the 400 meters, males got only about 40% of their energy during the race from the aerobic system (60% from the anaerobic system).  Therefore, in running the 400 meters, a significant amount of aerobic conditioning is required.  Aerobic energy systems are very efficient in that ATP (molecular biologic energy) is produced in large amounts per Oxygen utilized.  Anaerobic energy systems are very inefficient.  In terms of burning calories, then, being inefficient is ideal.  Anaerobic energy systems acquire ATP from that which is stored directly in the cells (about 5 seconds worth) in the form of ATP and creatine-phosphate forms which can rapidly donate phosphate to ADP to form more ATP (another 15 to 20 seconds).  Anaerobic metabolism can also produce small amounts of ATP from glucose (glycolysis).  This can get you out to 30 to maybe 40 seconds of very high intensity energy output.  The downside to this form of ATP production is that the by product is lactate.  This lowers intracellular and blood pH, (makes a more acidic environment).  While a lower pH can result in vasodilation and improve delivery of Oxygen to tissues, as the pH drops further, enzymatic systems begin to be inhibited.  This leads to the inability to further convert raw materials (glucose) into energy.  As the ATP levels drop due to inability to maintain them, muscles fail to relax appropriately and you feel like you are running in water.  That is hitting the "wall" as it is called in longer sprints.

Studies have demonstrated that in exercise lasting longer than about 30 to 40seconds, trained athletes cross over to utilize predominantly aerobic energy systems.  In summary, to achieve the best 400 meter time possible, it is important to get a fast start and cover a good distance in the first 30 to 40 seconds.  The best sprinters easily cover more than 200 meters before they begin to move to the aerobic energy system.  The world record in the 400 meters is in just over 40 seconds.

Training can improve the recover and efficiency of the anaerobic pathways.  Anaerobic conditioning is also phenomenally effective in burning unwanted calories and producing a sleek and toned physique.  Recently, there has been a large amount of data demonstrating the benefits of High Intensity Interval Training (HITT).  For a long time the preconceived notion was that to burn fat (or lose unwanted pounds), you should work out in the aerobic threshold (about 60 to 70% of maximum capacity) over a long period.  However, HIIT, (working out in the anaerobic zone) can increases both aerobic and anaerobic capacity, burns fat, and increases VO2 max.  The incredible thing about HIIT, is that you can accomplish a lot in a little amount of time.
The Speed Strength Combine is very much a test of anaerobic fitness. Nevertheless, the training required to achieve competitive scores will indeed produce great results in aerobic conditioning as well.