Aerobics classes are a specialised form of exercise aimed at strengthening the body's cardiovascular system without overly stressing any particular part of the body. It involves a lot of bodily movement (of course), but the movement is designed to be not overly repetitive. As such, it often involves a lot of specialised choreography, which is intimidating to beginners.

Nonetheless, aerobics is an attractive form of exercise. Women like it because aerobics classes burn calories and doesn't lead to grotesque musculature. Men like it because aerobics classes contain lots of women.

This entry is intended to introduce a beginning student to aerobics classes.

The Definition of Aerobic Exercise

There are two major categories of exercise: aerobic¹ and anaerobic². These are based on two forms of chemical reaction that produce energy within the human body - one form requiring oxygen, one not. The aerobic form that requires oxygen includes all casual activity as well as all activity that doesn't exhaust the muscles.

Anaerobic exercise is the opposite of aerobic exercise. (Well, actually, no exercise is the opposite of aerobic exercise, but hopefully you get the idea.) It occurs when a part of the body's muscle tissue runs out of oxygen stores during exertion. The lack of oxygen exhausts and slightly tears apart the muscles, forcing them to rebuild with more mass. Weight lifting is an example of anaerobic exercise. As may be imagined, aerobic exercise is a prerequisite for anaerobic exercise. You have to burn the oxygen, before you can run out of it.

The body's cardiovascular system consists of the lungs, heart and veins. These are the body parts which get oxygen to the muscles. The better the cardiovascular system works, the longer the body can last before it has to draw on anaerobic energy reserves. Aerobic exercise is meant to reinforce this system, thereby enhancing the body's endurance.

The usefulness of aerobic vs anaerobic exercise is debated. Anaerobic reactions are better for building strength, but aerobic reactions release ten times as much chemical energy. Really, it depends on what you want from your exercise. To put it as simply as possible: for strength, go anaerobic; for endurance, go aerobic.

What an Aerobics Class Contains

Kinds of Aerobics Exercise

There are two major kinds of aerobic exercise offered in classes.

• Step aerobics uses a step or riser to stress the leg muscles somewhat. The step is roughly four feet long by two feet wide by six inches high. Risers can make it up to one foot tall.

• Floor aerobics involves moving around on the ground. It's usually titled something like 'Cardio Challenge' to make it sound more exciting.

In recent years, step aerobics has been more popular than floor exercises. This is largely because step aerobics classes can play slower music and get the same cardiovascular benefit. Plus, step aerobics actually involves 'work' by the muscles in the gravitational sense³. Many gyms now offer only step aerobics, not floor.

Kinds of Aerobics Impact

Aerobic exercise can be either high or low impact.

• Low-impact - This exercise keeps at least one foot on the ground (or something which at least touches the ground) at all times.

• High-impact - This exercise involves having both feet off the ground sometimes. In other words, there's jumping or running of some sort is involved. It provides more cardivascular benefit than low intensity, but it also stresses bones and joints more, which is a bad thing for many people. Stressed muscles recover quickly; stressed bones, joints and tendons recover slowly, if ever.

Typical aerobics classes allow students to choose either high or low impact. The teacher demonstrates low impact first. Students can then keep doing that or do the high-impact version which the teacher demonstrates next.

Kinds of Aerobics Classes

While there may only be two kinds of exercise and two kinds of impact, there are many variations.

• Floor or Step is the basics of that form of exercise.

• Interval internal means two types of workout mixed together, as in 'step interval'. This means you do step aerobics for a while, then weights for a while. Repeat until the class is over. Different weight-lifting exercises are used in each interval, to exercise a wide range of muscles.

• Circuit is similar to interval, except that the exercisers move to stations around the room, trying out different types of exercise.

• Hi-Lo is where students are expected to mix high and low-impact aerobics, whenever the teacher commands. Remember, though, you can always stick with low impact.

• Muscle Conditioning is, in other words, weightlifting. The main difference between these classes and the weightlifting room is instruction. A teacher will instruct you on the use of your hand weights during these classes.

• Boxercise and kickboxing are forms of martial arts and have been noted as good aerobic exercise too. Kickboxing is especially good for the legs, which matches the emphasis of most aerobics classes. Even straight boxing involves a lot of leg movement, so aerobics teachers have started teaching boxing and kickboxing. However, if you want to learn effective fighting form, these classes are usually not for you.

• Step kickboxing classes combine step aerobics and kickboxing. These are popular, but virtually useless for fighting form as well, unless you do all your fighting on soapboxes, but it will make you work up a sweat.

• Slide exercisers put on some slippery booties and slide back and forth on a three-foot slick surface. It's sometimes known as 'ski conditioning', because the motions vaguely resemble skiing. An hour of this may not make you sweat, but you'll feel it in some of your leg muscles that never get exercised otherwise.

Sequence of an Aerobics Class

No matter what kind of class, there are fairly strict rules on how the class is sequenced. These rules help protect the students from injury and heart failure.

1. Warm-up - About five minutes of movement done with low intensity, usually on the floor (not the step - opinions differ on whether using the step during a warm-up is safe). This section is intended to limber the muscles for later use.

2. Stretches - About five minutes of stretches, intended to lengthen the muscles for later exertion. This follows the warm-up so the muscles will stretch better. (Muscles, like Rubber bands, stretch farther when warm.)

3. Aerobics - This is the main segment of the class, lasting 35 to 40 minutes. This follows stretches so the muscles are less likely to reach their limits of extension. The tempo and intensity of movement gradually increase throughout this segment.

4. Cooldown - About five minutes of movement done with gradually decreasing tempo and intensity. This is better for the circulation than an immediate full stop, because during aerobic exercise blood tends to pool in the muscles where it's needed. Moving muscles helps pump blood back in the heart where it belongs.

5. Drills - Something which emphasises a particular set of muscles. Abdominals (the stomach area) are a favourite, because most exercisers think that stressing that muscle will make it grow smaller⁴, but lunges, squats, and lopsided marches (one foot on the step, one on the floor) are also popular. These usually last five minutes, but some instructors devote entire classes to this stuff.

6. Final Stretches - About five minutes of intensive stretching. This helps avoid muscle tightness after the intensive exercise.

Aerobics Terminology

Aerobics classes use a specialised set of manoeuvres with a specialised vocabulary. There are too many manoeuvres to be easily listed, but some of the most common can be found on the web. An Introduction to Aerobics Choreography can be found here.

Don't try to learn the terminology before class. Just do what you see the other students doing.

How to Take an Aerobics Class

There are some important rules for the student to follow. Failure to observe these rules can cause major bodily dysfunction, which the instructor wants you to avoid as much as you do. Don't panic. These rules are common sense and apply whether the instructor explicitly says so or not. (Instructors may be too busy pushing the other students hard to pay attention to whether you're about to die. Instructors are supposed to notice you dying, but, let's face it, you have more of a vested interest in that matter.)

• Get water when you need it - Dehydration is bad.

• Do things at your own level - Tripping or having a heart attack is bad.

• Have fun - Doing something you hate is bad.

Shrug and Keep Moving - a Good General Rule

• As mentioned earlier, aerobic exercise is intended more for the cardiovascular system than for specific muscles. So, if you do one thing while the rest of the class is doing another, it won't really matter to your fitness level. Just shrug and keep moving.

• Public aerobics is much like public humiliation at first, but nobody else will be laughing at you (or, at least, they'd better not be) because they've all been there. Besides, it's not as if you're making them look bad. When you screw up, just shrug and keep moving.

• Your instructor will screw up during class at least once. As hard as it is to be a student, imagine having to do all the manoeuvre and know what's coming next and announce it beforehand and not run out of breath. When the instructor screws up, just shrug and keep moving.

About a month after your first class, you'll finally start to get it. About a year later, you can be good enough for people to suggest that you yourself become an aerobics instructor.