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Cross Training

2008-05-15来源:

One of the biggest misconceptions about exercise is that there is "one" program that works for someone all the time. People think that they need to get on a particular workout program and just keeping doing that program over and over again. Although getting on a good program IS a necessary first step, ensuring that your body doesn't adapt to that program is critical to ensuring that your results don't slow down or stop!

In order to maintain the effectiveness of your workouts over the long term, you have to employ a concept known as cross training. Although there is no hard and fast definition of cross training, the basic idea is that you continually change your exercise program to work both your muscular and your cardiovascular systems in a variety of ways, forcing your body to adapt to a new stimulus. Remember that the whole idea behind exercise is to make your body do things that it is not used to doing. In response to that effort, your body naturally adapts in order to meet the changing energy demands of the activities that you engage in. This process happens with your muscles, as well as with your heart, lungs, and circulatory system - collectively known as the cardiovascular system. To ensure you get the most out of your cross training efforts, you should make changes to the activities that challenge your muscles as well as your cardiovascular system.

Challenging Your Muscles

When you are putting together the muscular training part of your exercise program, remember that the primary mission of the activities is to challenge your muscles and connective tissues - tendons and ligaments - beyond their normal boundaries. For example, if you were to pick up a suitcase that only weighed 5 pounds, it would probably not be very difficult for you. However, if that same suitcase had 50 pounds worth of items inside, it would be significantly more difficult to pick up and carry. In response to that increased demand, your body would recruit additional muscle fibers to assist with the work, and in some cases would even recruit a different type of muscle fiber. Although we won't get into the details about the different types of muscle fibers in the human body, you do want to take away the fact that the number and type of muscle fibers recruited for any given task is proportionate directly to the difficulty of the task.

Let's apply this concept to weight training - or resistance training, as it is often called. If you were going to do a basic bicep curl with 5 pounds, your body would engage a certain number and type of muscle fibers. Doing exactly the same exercise with a more challenging weight would cause your body to need additional resources in order to handle the increased demand. However, is that only true of picking up a heavier weight? What would happen if you used the same weight, but did a higher number of repetitions? The same basic concept applies - your body will recruit additional resources in order to accomplish the task. What can be determined from that fact is that in order to change the stimulus on your body, two easy ways to do so are are to increase the weight and/or increase the number of repetitions.

However, there are other ways to challenge a particular muscle group in addition to simply adding weight or repetitions. What about changing the position of your body when you do the exercise? Using the same example as above - the bicep curl - most people do the basic version of that exercise standing up, with their arms extended, elbows at the side, and palms facing forward. What if you were to do the same exact movement, only this time, you turn your palms to face the center of your body throughout the entire exercise? Do you see how that would change the stimulus? You would still be engaging the biceps of your upper arm, but you would also engage the muscles of your forearms in a different way, just because of the position of your palms.

Further, what if you were to change the speed at which you did the exercise? Most resistance exercises should be done as a basic count of 2 seconds during the initial phase (also known as the concentric phase), and then a count of 3 to 4 seconds during the second phase of the movement (known as the eccentric phase). What if you were to reverse that process? Count to 4 during phase one, and only count to 2 during phase two. Do you think your body would need to react differently to handle the different stress? Of course!

There are many, many different kinds of exercises for the biceps. If you normally do bicep curls, hammer curls, and cable curls, what would happen if you started using 2 or 3 of the bicep curl machines instead? Your body would have to adapt to the new stimulus! By sitting down in a bicep curl machine, you are no longer using your leg, back, and abdomin