April 22nd, 2011
03:22 PM ET
Every weekday, a CNNHealth expert doctor answers a viewer question. On Friday, it's Dr. Melina Jampolis, a physician nutrition specialist.
Asked by Nick E., Menomonie, Wisconsin
I'm 23 years old and a fairly active person who has been in training as an amateur boxer for some time now, and I'm trying to improve my cardiovascular strength and stamina. I've been running outdoors quite regularly (every day to every other day), but I seem to have "topped out" my cardio strength. I was wondering if there is a more effective way to further improve on this. Is it better to run longer distances but at less intensity or vice versa? Do you have any other recommendations?
Hi, Nick. Depending on how serious you are, you may want to consider seeing an exercise physiologist for a thorough physiological assessment, including metabolic testing (e.g., VO2max, lactate threshold).
This can help you more objectively assess your cardiovascular fitness and determine optimal heart rate training zones for improving fitness and endurance.
The widely available equations for calculating heart rate training zones may not be specific enough to help you significantly improve performance, but they do provide a starting point, and when combined with a heart rate monitor, they can help you more accurately assess and monitor the intensity of your training sessions.
I find that many of my patients overestimate how hard they are working during workouts. Checking your heart rate, whether using a monitor or simply feeling your pulse immediately after a workout, can provide valuable information as to how hard you are working.
I consulted with a group of exercise physiologists, and based on the information you provided, they suggested the following:
• Mix it up between very low intensity and very high intensity
• To improve maximal aerobic fitness, all athletes need some aerobic base, regardless of the event. Spending time building a base is best at a lower intensity. Slow way down and run longer.
Even for a boxer, 45 minutes to an hour running very slowly (slow jog), out of season (months before a big, focused fight), will create a much higher level of aerobic fitness that will allow him to have more energy for longer periods of high intensity training/boxing.
• As a fight gets closer, the slow running needs to be reduced in overall training because it will slow you down neuro-muscularly. Work on some shorter bouts of higher intensity running to improve high-end cardiovascular development. This has to be worked around sport-specific high intensity training, not supersede it.
• A good example of a workout might be something like this: Warm up with an easy jog of 15 minutes, 2 x 200 meters at high intensity, recover fully between each rep, 2 x 400 meters, 1 x 800 meters, then finish with 2-4 x 100 meters sprinting. Cool down 15 minutes.
I hope this helps and again, to get more specific information, I recommend you consult an exercise physiologist who can more accurately tailor a workout to your needs.
Note that the idea of mixing up workouts also applies to weight loss. I find that many of my patients are able to break through weight loss plateaus by varying the intensity, type and duration of workouts on a regular basis.
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