What follows is an excerpt from the Geek Out section of my book, Simple Marathon Training. Enjoy!

Pool Walking for Runners – Dr. Richard Hansen

Standing on the starting line of any race, it’s natural for runners to run down the checklist of, “How does my body feel, and will it do what I hope it can today?” Soreness is a natural and common occurrence with any training plan. It’s the response of our bodies trying to adapt to a new stimulus. When soreness lingers or the sensation turns to pain, it can inevitably raise concerns that the goal on race day is slip sliding away.

Reduce this fear by utilizing one of the easiest and most efficient recovery tools: pool walking. A pressure gradient is created the deeper your tissue is below the surface, which helps to prevent pooling of inflammation and move lymphatic fluid. For example, if you are standing at a depth of 4.5 feet of water, you are creating a pressure gradient equivalent to 77 mmHg at your calf (approximately 3.5 feet below the surface). This is over 2x greater than standard graduated athletic compression socks or sleeves (which are usually around 22-32 mmHg). Now, add walking to this equation and you create a joint pumping mechanism called imbibition to help mobilize the joint and further aid circulatory flow.

Additionally, pool walking can provide a valuable benefit in assisting muscle repair following a hard workout. Resting blood flow response in muscles has been shown to increase from 1.8ml/min/100g of tissue not in water compared to 4.1ml/min/100g in water. This means that pool walking is 225% more efficient at assisting oxygen supply to muscle tissue than walking on dry land, which is a crucial process for tissue repair.

Aqua therapy is also a commonly used rehabilitation practice for spinal cord injury patients due to a reduction in pain threshold noted when irritated tissue is submerged. Following intense bouts of running exercise, over-stimulus of the nervous system is a common occurrence. Having the ability to calm down the nervous system following intense or prolonged workouts can improve pain perception and decrease tissue sensitivity.

The challenge is finding time to get to the pool or finding access to a pool in your area. Try to pair pool walking days with workout days requiring gym equipment (e.g., squat racks, elliptical machines, free weights, etc.). This way the trip to the gym can be multi-faceted, saving you time and money. Keep yourself healthier by utilizing one of the most efficient and effective recovery tools available – the pool!