Physioinfo Article

Pool Running

Pool Running ? Not Just for Rehab! Most athletes and specifically runners are first exposed to pool running due to injury. Whether it be from running too far, too fast or simply too much pool running or deep water running (DWR) provides a non impact alternative to running that can help maintain fitness. It is important to maintain an active rest during injury and work completed by Dr. Jack Daniels (author of Daniels? Running Formula) identified a few important points: first, there is almost no drop in fitness as a result of missing up to five days of running. Following that, your conditioning drops more significantly and then levels out after about ten weeks, which would represent your baseline fitness as a sedentary individual(1). After about a week or two of not running, the differences between an individual that cross-train (by any means) and one that takes complete rest emerges. After fourteen days the difference is about two percent but then increases to ten percent (80% of initial fitness vs. 90% of initial fitness) after ten weeks or more. This means that a 4:30 miler who takes 10 weeks completely off will (in theory) regress to 5:32 without cross-training, but only 4:57 with it(1). So why choose DWR or other cross training alternatives? Unlike cycling or the elliptical, DWR is quite similar to over-ground running in terms of the muscles used and the range of motion. However, pool running has benefits far beyond a strictly rehabilitation role and athletes should not assume that aquatic training only benefits those during injury rehabilitation. Running in water is a great way to reduce the chance of overuse injuries associated with high volumes of running. Also, due to the drag associated with running in water, an element of resistance training is associated with water running that does not exist in over-ground running-based training(2). Additionally, on land you will use essentially the same muscles to lift and lower as you work against gravity in both cases. But water offers resistance in every direction, forcing you to use the opposing muscle ? triceps instead of biceps, for example ? during arm swing. This prevents muscle imbalances from developing, and also prevents muscle soreness, which is usually associated with the eccentric muscle contractions involved in the lowering phase of muscles during on land running. (3) Lastly, the water?s buoyancy also means that you?re only bearing about 10 per cent of your usual weight if you?re immersed to your shoulders. This decreases compression on your joints, eliminating the thousands of impact-producing foot strikes incurred during land running which further reduces the chance of injury (3). DWR Technique: Only the tops of the shoulders, neck, and head should be above the surface of the water with your feet not touching the bottom of the pool. A flotation device will be necessary to preserve ?normal? biomechanics (4). If a flotation device is not worn, body position can become compromised and an undue emphasis is placed on the muscles of the upper body and arms and a high knee gait with a rapid stride turnover will be needed to keep the body afloat. (4, 2) The head should be centered with a slight lean forward at the waist with the shoulders pulled back, not rotated forward. Elbows should be bent at 90 degrees, with movement of the arms driven by the shoulders. The wrists are held in a neutral position, and the hands, although not clenched, are more closed than on dry land in order to push through the resistance of the water(4). Leg action is more akin to faster-paced running than general aerobic running because of the propulsive force needed for overcoming the resistance caused by the density of the water. The knee should be driven upward to an approximate 75-degree angle at the hip. The leg is then driven down to almost full extension (avoiding hyperextension) before being pulled upward directly under the buttocks before the process is repeated with the other leg (4). Example Workout Aqua jogging should be done at the same intensity, duration, and frequency as your normal training. So, if your training schedule called for a 90-minute long run, it can be a long hour and a half in the pool(4)! An example of a challenging hour-long workout completed by Canadian mile record-holder Kevin Sullivan hour-long workout to maintain fitness while recovering from a stress fracture in his sacrum before the 2002 Commonwealth Games (3): Hard/Easy 5 minutes/2.5 minutes 4 minutes/2 minutes (x2) 3 minutes/1.5 minutes (x3) 2 minutes/1 minute (x4) 1 minute/30 seconds (x5) 30 seconds/15 seconds (x6) 15 seconds/10 seconds (x7)