Exercise BallsThere are many Exercise Balls of various sizes on eBay. They are sometimes referred to as Pilates balls which refers to an exercise style that calls for their use. Many exercise balls are listed as being "burst resistant" and that they have various maximum weight ratings which exceed 500lbs. or more. The following article is the result of research conducted on thirty exercise balls purchased on eBay. While there are no industry standards for testing exercise balls, numerous tests were conducted relating to the inflation pressure and weight tolerance. The tests resulted in the bursting of twenty two balls.
Selecting Proper SizeIn exercises using an exercise ball, the size of the ball should be appropriate to the height of the user. It is best to consult a fitness professional in selecting which size ball is appropriate for a particular user.
Selecting Proper Size for Sexual UsesSome people also use these balls for positioning during sexual intercourse. In this application it is generally better to select a ball slightly larger than what is needed and adjust the level of inflation to fit the required size. A slightly under-inflated ball will also be somewhat more bouncy than a fully-inflated ball.
Exercise balls used in sexual intercourse should not be used on a bed since the inherent bouncy nature of the bed makes the balls unstable and can send the people using the ball crashing to the floor. This data is based on interviews with test subjects that used an exercise ball for sexual intercourse. The test subjects had an aggregated weight of approximately 500 lbs. and did not burst any exercise balls in the course of using exercise balls in sexual intercourse.
Weight ToleranceThe weight tolerance of exercise balls is not a reliable measure of the actual load bearing capacity of the ball. Since the surface area of the weight applied to the ball and the surface on which which the ball is tested can vary, there is no reliability in these weight ratings. Exercise balls are best used on a clean, carpeted or padded floor.
Burst ResistantThe "burst-resistant" designation generally has little meaning since all exercise balls have similar properties regarding their resistance to bursting. The general level of quality in manufacture can vary widely, even within the same brand. Many exercise balls are manufactured by contractors in the Far East and marketed by companies with little or no oversight of the manufacturing process. It is not uncommon to have two balls of the same brand and rated size, that when fully inflated, are different sizes.
The level of resistance to bursting that an exercise ball has, is most related to its level of inflation. Compare an exercise ball to a similar object, a toy balloon. Many people have observed what happens when people try to burst toy balloons by sitting on them. Sometimes the balloons burst immediately and other times the balloons must be sat upon repeatedly in order to burst them. Toy balloons have no weight rating or make any claim of burst resistance, but yet some are more difficult to burst than others. This is mainly due to the level of inflation of the balloons.
Due to the lack of oversight in the manufacturing process of exercise balls and how balls can vary in size, even when they are the same rated size, can be over-inflated even when they are not inflated to their rated size. A ball that is fully inflated, can be dented with thumb pressure to a depth of one half inch. This is the only reliable method of determining if the ball is fully inflated. Inflating the ball with measured air pressure is of little value since exercise balls can be burst with only 5 PSI of air pressure.
Exercise Ball InflationThere are a number of inflation options available for inflating exercise balls including: hand pumps, foot pumps, electric inflators, compressed air and an improvised electric inflator. Many exercise balls come with hand or foot pumps for inflating the ball. Hand pumps are the least efficient means for inflating exercise balls. Foot pumps are much faster, but are also somewhat of a workout in and of themselves.
Electric inflators, which are commonly used for pool toys and toy balloons can also be used. In general, electric inflators are the best for inflating exercise balls since they provide the high volume of air needed to inflate an exercise ball while only delivering a small amount of air pressure and avoid bursting the ball.
Compressed air that is ordinarily used for inflating automobile tires and powering shop tools can also be used and is the fasted method of inflating exercise balls. Inflating exercise balls with compressed air requires caution since it is very easy to over-inflate the ball. An over-inflated ball generally will not burst immediately like a toy balloon, but rather burst by a delayed reaction since the ball expands more slowly than you can pump air into the ball. Delayed reaction bursting can occur anywhere between a few minutes and several hours depending upon the amount of pressure that the ball is over-inflated with.
It is possible to improvise an electric inflator using a vacuum cleaner on reverse. Simply put the nozzle of the vacuum cleaner's hose over the inflation hole of the ball and start inflating the ball. The nozzle need not fit into the inflation hole, but merely it over it. The air will flow into the ball. It should be noted that this method likely puts more back-pressure on the vacuum cleaner's blower than it was intended to have and the motor of the vacuum cleaner should be monitored so as to avoid over-heating of the motor.
To achieve full inflation of an exercise ball, the ball should be inflated until the the ball can be dented with thumb pressure to a depth of one half inch and then plugged and allowed to sit overnight. Then the ball should be checked again with the thumb pressure test and inflated more if needed. Each time the ball is further inflated, it should be allowed to stand overnight.