A runner that I coach actually PR'd at a 1/2 marathon after only 4-weeks of running! In the month prior, she was water running, cycling, and using an elliptical trainer as she recovered from a broken toe. Fortunately, you don't have to break your toe for cross training to work for you too!
As runners, there has been a great deal of information regarding the importance of cross training aimed your direction. Of all of the reasons that have been given, reducing the chances of over- use injuries would probably be the single most important one of all. As any serious runner knows, injuries are never good for you. With that in mind, learning from your mistakes (or others') is what can make you both a smarter and faster runner.

Coming from a multi-sport background, cross training is the basis of my training as a triathlete. I would contend that cross training is not only good for runners...it is essential to include in your training if you want to be the best runner you can be. The foundation of performance for any endurance athlete is your level of aerobic fitness. Simply defined, aerobic fitness is the ability of your body to take in and extract oxygen from the environment to produce energy within our muscles. The more energy we can produce, the more work that can be done - period. For runners, the work that we do is, well, running.

To run faster requires you to do one of more of the following:
1. Produce more energy from the aerobic system
2. Improve muscular endurance and lactate tolerance
3. Expend less energy to run a given pace

Improving your running technique will help you improve #3. Points 1 and 2 can be improved not only with running, but also by cross training!

Many runners have heard about periodization, or simply put - altering the intensity of your training over time. As many coaches in the world of endurance sports believe, the volume of your aerobic foundation is what enables you to reach your true potential as an endurance athlete. This aerobic foundation is built not only within each season, but continues to improve for years with proper training. The best part of this aerobic foundation is that you can build it by doing more than just running! Any activity that is sustained and aerobic can help you build your aerobic foundation. Some basic examples include: bicycling, hiking, snowshoeing, and cross-country skiing. The best time to use these alternative exercises is during the off- season to maintain aerobic fitness while taking a break from running, and during your base building season as your training volume (hours of exercise each week) is increasing. All of this allows you to effectively train more, with less impact and injury potential for your legs!

Depending on your race schedule, your base training should probably begin in January. Luckily, for those of us in Colorado there are lots of winter cross training activities available to help improve our aerobic fitness during the base season. If you're starting with a new activity, be sure that you are using safe equipment and start off using proper technique. Going hard is not necessary! All of your base training work should be primarily aerobic, e.g. at conversation pace. The low intensity work will help build your muscular endurance, improve the body's ability to use fat as a fuel, and help reduce the amount of lactic acid that the body produces at higher speeds. Building your base will pay dividends down the road.

For bicycling, make sure that your bike is tuned, you always wear a helmet when riding outdoors, and your bike fits you. For cross-country skiing, make sure that your equipment is all in good condition and take a lesson or two to be sure that you are using proper mechanics. In cross-country skiing, there are two basic styles: classic or diagonal stride, and skating technique. For snowshoeing, all you need is a pair of snowshoes and some snow. Hiking in snowshoes and regular hiking are better base training activities than running in snowshoes, as the intensity is much lower - unless you are super fit!

During the base season, I know many endurance athletes that spend about 1/2 of their training on cross training activities. As the spring comes closer and the racing season nears, the amount of cross training decreases. To prolong your fitness and running performance, aim toward maintaining about 10-20% of your training volume in sports other than running. Often, I encourage the single-sport athletes that I coach to use cross training to more effectively recover from hard sessions and races (example: easy bike ride the day after a race), and also to add in an extra intensity day for those who are more injury prone. Expanding your horizons on cross training is not only good for the body - but also great for your mind! Learning a new skill and seeing different scenery are two more great reasons to get out there and cross train your way to better performances in 2004!

Neal Henderson is a professional triathlete, expert coach, and the Coordinator of Sport Science at the Boulder Center for Sports Medicine. He is the ultimate cross trainer and can seen across the U.S. competing in endurance sports ranging from 5Ks to winter triathlons. He can be reached at nhenderson@bch.org.