Mix it Up with Cross-Training

As the public’s knowledge about the benefits of exercise continues to grow, so does the demand for diversified programming. Not only must fitness programs appeal to a wider group of people than ever, but they must also be varied enough to hold the interest of exercisers and to promote overall fitness without injury.

The best way for health clubs to meet this need is through the development of cross-training programs. From a clinical standpoint, cross-training enables individuals to place significant demands on the heart and circulatory system, since it typically involves aerobic-type activities. Cross training produces increased cardiac output, blood volume and a greater number of red blood cells, which ultimately enhances the body’s ability to transport oxygenated blood to the exercising muscles.

In response to engaging in aerobic-type cross training on a regular basis, several significant changes take place within the muscle cells.

* The number and size of mitochondria (organelles in the muscle cells that produce ATP for energy) increase.

* The amount of glycogen (carbohydrates) stored in the muscle increases.

* Concentration of important enzymes (within the mitochondria that are involved in the production of ATP) increases.

* The amount of triglycerides (fat) stored in the muscle increases.

* The ability to oxidize fat from primarily muscle-fat stores, but also from adipose tissue stores, increases. This enhanced ability to use stored fat results in less glycogen depletion, less lactic acid accumulation and, concomitantly, less muscular fatigue and better endurance.

These changes, called peripheral adaptations, help the muscles contract repeatedly and more efficiently during exercise. Peripheral adaptations are activity-specific (i.e., they differ from activity to activity). For example, trained distance runners cannot transfer their high level of endurance for running to swimming because the peripheral muscular adaptations required for optimal performance are different for swimming.

The combined effect of peripheral and central adaptations determines the quality of performance. Improving one without the other, however, produces limited improvements in sport-specific performance. Accordingly, while cross training may offer certain advantages for the typical fitness enthusiast, it may also have a few limitations for competitive athletes. As a result, individuals who know exactly what they want from their exercise efforts are better able to decide whether to engage in cross training.

The benefits of Cross-training

Incorporating several different forms of exericse in a training program can be an excellent way to develop various components of fitness. The following are among the numerous benefits of cross training that have been documented.

* Reduced risk of injury. By spreading the cumulative level of orthopedic stress over additional muscles and joints, individuals are able to exercise more frequently and for longer durations without excessively overloading particularly vulnerable areas of the body (e.g., knees, hips, back, shoulders, elbows, and feet). For example, individuals who are particularly prone to lower-leg problems from running long distances should consider incorporating low-impact activities such as arc trainers, cycling and swimming into their regimen.

* Enhanced weight loss. Individuals who want to lose weight and body fat should engage in an exercise program that enables them to safely burn a significant number of calories. Research has shown that such a goal, in most instances, is best accomplished when individuals exercise for relatively long durations (i.e., more than 30 minutes) at a moderate level of intensity (i.e., 60 to 80% of maximal heart rate). Overweight individuals can safely enhance weight and fat loss by combining two or more physical activities in a cross-training regimen. For example, such a person can exercise on an arc trainer for 20 to 30 minutes and then cycle for an additional 20 to 30 minutes.

*  Improved total fitness. Cross-training can include activities that develop muscular fitness, as well as aerobi conditioning. While an individual’s muscular fitness gain will typically be less than if he/she participated only in strength training, the added benefits of improving muscular strength and endurance can pay substantial dividends. For example, research has demonstrated that sound resistance training can help individuals prevent injury, control body weight and improve functional performance capacity.

* Enhanced exercise adherence. Research on exercise adherence indicates that many individuals drop out of exercise programs because they become bored or unmotivated. Cross training is a safe and relatively easy way to add variety to an exercise program. In the process, cross training can hellp play a positive role in promoting long-term exercise adherence by eliminating or diminishing the onset of boredom.

Cross training guidelines

Whether individuals exercise for fitness or because they are competitive athletes, the essential fundamentals of cross-training are the same. Individuals can choose to vary their exercise programs from workout to workout by engaging in different types of activities, or they can simply add a new form of exercise (e.g., resistance training) to their existing exercise regimen.

One of the easiest ways to incorporate cross training is to alternate between acitivities (e.g., run one day, weight train the next, cycle the next, etc.) Exercisers can also alternate activities within a single workout (e.g., walking on a treadmill for 10 minutes, exercising on a stationary kayak for 10 minutes, and cycling for 10 minutes — for a total of 30 minutes of exercise).

Making a cross-training program effective is basically a function of adhering to established exercise guidelines. If individuals engage in 20 to 60 minutes of aerobic exercise at least three days a week at an intensity of approximately 60 to 90 percent of maximum heart rate, they will become more aerobically fit. At a minimum, according to guidelines published by the American College of Sports Medicine, individuals should perform at least eight to ten exercises that condition the major muscle groups of the body twice a week to enhance muscular fitness.

Mixing it up. From the moment the first person engaged in and exercise workout, mankind has been searching for a “better” way of training. Apparently, nothing has been held sacred in the pursuit of the best way to achieve maximal training results– new conditioning tools, new exercise prescriptions, new training environments, new levels of hands-on assistance.

In the past 30 years, a substantial number of exercise enthusiasts have discovered cross-training to be another “new” improved method to exercise. Unlike many previous attempts to discern how to improve training, cross training has been found to be a highly-safe, relatively enjoyable method. In fact, most cross-training enthusiasts proudly proclaim that “they’ll never go back” to single-activity training. To these individuals, many of the inherent problems that occur in a standard exercise regimen can be easily remedied by adhering to the advice: “If your workout needs fixing, fit it up by mixing it up.”

Daryl Conant