An apparatus or device used in any given physical activity for shaping and forming muscle groups for specific areas of the body. A mechanism or machine that is intended to promote health and fitness by using motion with varying degrees of resistance either fixed or adjustable.

Exercise balls

Exercise balls are available in a number of forms. There are large Pilates balls

Swiss ball

An exercise ball is a ball constructed of soft elastic with a diameter of approximately 35 to 85 centimeters and filled with air. The air pressure is changed by removing a valve stem and either filling with air or letting the ball deflate...

 specifically suited to Pilates

Pilates

Pilates is a physical fitness system developed in the early 20th century by Joseph Pilates in Germany, the UK and the USA. As of 2005, there were 11 million people practicing the discipline regularly and 14,000 instructors in the United States....

 exercises. Medicine balls are somewhat larger than a basketball and are used as a training aid for a variety of different exercises. There are also a number of different types of timing balls used in developing accuracy and timing of martial arts strikes and kicks.

An exercise ball can also be used to help treat low back pain

Low back pain

Low back pain or lumbago is a common musculoskeletal disorder affecting 80% of people at some point in their lives. In the United States it is the most common cause of job-related disability, a leading contributor to missed work, and the second most common neurological ailment — only headache is...

 and to prevent future back pain episodes. The ball helps by strengthening and developing the core body muscles (the belt of abdominal and back muscles) that help to stabilize the spine (or vertebral column

Vertebral column

In human anatomy, the vertebral column is a column usually consisting of 24 articulating vertebrae, and 9 fused vertebrae in the sacrum and the coccyx. It is situated in the dorsal aspect of the torso, separated by intervertebral discs...

). An exercise ball creates instability to the exercise that normally wouldn't be there, forcing the body (and the core) to keep balanced. This strengthens the muscles that are doing the balancing.

Exercise balls work for many types of athletes, including older people and pregnant women. There are specific exercises developed for use with the ball that are appropriate for these and other special interest groups.

Weights

Weights come in many forms, machines, Bulgarian Bags

Bulgarian Bag

The Bulgarian Bag , also known as the Bulgarian Training Bag , is a crescent-shaped exercise equipment used in strength training, plyometric weight training, cardiovascular training, and general physical fitness...

, dumbbell

Dumbbell

The dumbbell, a type of free weight, is a piece of equipment used in weight training. It can be used individually or in pairs .-History:...

s, medicine balls, kettlebells, sandbells, and barbells. A dumbbell is a small bar with weights on either end, and is held in a single hand, a barbell on the other hand is a large bar with weights on both ends, and both hands are used to grip it.

Dumbbells and barbells are both useful for exercising different muscle areas and maintaining safety throughout a workout, but machines are both safe and also what is known as an isolator. Machines usually only have one path of motion, meaning that it follows a direct path through a system of pulleys and/or attachment to an immobile frame. Some examples of weight machines are Smith Machine

Smith machine

The Smith machine is a piece of equipment used in weight training. It consists of a barbell that is fixed within steel rails, allowing only vertical movement. New variations allow a small amount of forward and backward movement. A Smith machine often includes a weight rack in the base to help...

s, leg press

Leg press

The leg press is a weight training exercise in which the individual pushes a weight or resistance away from them using their legs. The term leg press also refers to the apparatus used to perform this exercise...

 and Mechanical Shoulder Press.

Homemade Weights

Sandbags of various weights, water-filled kegs, ropes, tractor tires and generally other heavy objects can be used for exercise. These more awkward weights and exercises utilize even more muscles, such as forearm muscles involved in gripping the weights. Each of these are examples of free-weights that are exercised with while standing and incur full body impact. These are alternatives to store-bought weights and can be made on a budget. Sandbags and kegs can be filled to various weights and tuned for the individual exercise practitioner.

Rowing Machines

There are a few different types of rowing machines that are classified by resistance. Different form of resistance offer different workouts for the individual using them. The hydrolic rowing machine uses pistons to form resistance for the user. This is often the least expensive form of rowing machine. Water Rowing machines use water as the resistance source and are often considered the best rowers by many because of the natural feel they give. Flywheel or air rowing machines have been in existence for years. They use the resistance of air to provide a solid workout. The one downfall to flywheel rowing machines is they often put out a lot of noise due to the air movement. The last form of rowing machines is that of magnetic resistance. These are one of the most popular forms of rowing machine because they put out basically no sound. These machines work off of magnets that provide smooth transitions in and out of resistance levels. While most rowing machines are rather large there are some that fold easily to move out of the way.

Other equipment

Some other exercise equipment include: treadmill, exercise bike, cross trainer and cable pull down.