Well one of the most attractive points in using a Spa Hot Tub is the buoyancy effect provided by the water. Well for a minute we should consider what buoyancy is and why we can float in water.
It is simply that our specific gravity is lower than that of water. Specific gravity can be defined as the weight of the item in question divided by the weight of an equal volume of water so for example the specific gravity of water is one. Another way of putting it is that if the item in question when submerged in water has a weight lower that an equal volume of water then the object will float.
In perhaps a more simpler way one could say the when the weight of the water that you or the object in question displaces an amount equal to your weight or the object will float.
Well now we have had a brief physics lesson we can ask our selves what is the relevance of all this for a Hot Tub.
Well it is very important as the buoyancy effect and semi buoyancy depending on the seats and loungers in a Hot tub reduces the normal gravity effects on ones body.
This reduction and in some cases elimination of body weight has very considerable therapeutic effects on the human body.
This reduction in gravity provides very good support to any form of exercise including perhaps exercises for flexing and stretching ones joints and limbs.
Apart from the Buoyancy effect that water provides there are two other qualities that are very useful in a Spa these are known as Viscosity and Hydrostatic pressure.
Firstly dealing with Viscosity this is the measure of resistance of a fluid such as water. In simple terms the thin fluid like water will have a lower viscosity than say a thicker fluid like honey. Obviously we do not want to put Honey in a Hot Tub but the comparison is an apt one as the water will provide natural friction and resistance.
This combined with the Hydro Therapy provided by the Massage Jets in the spa it will allow you to get extra movement and relieve any aches or discomfort in your joints.
Secondly there is hydrostatic pressure and this means that some gentle movements can be a good way to strengthen lung and heart function. The hydrostatic pressure results in a gentle pressure on the body system and is able to increase the blood flow in the body. By so doing more life giving nutrients circulate to where they are needed.
The combination of these two principles combined with Hydro Massage Jets go a long way to explain why people get so much benefit from using a Hot Tub.