In the mountains of Japan there is a colony of macaques who spend time sitting in hot springs for protection against the cold. It is tempting to imagine a wise old macaque chancing upon the discovery and passing it on, so that generation by generation it became ingrained behaviour.

The macaques were onto something.

Bathing in hot springs has been part of human history from the very earliest times. There are numerous records of the practice, and there are many famous hot springs on every continent. The Ancient Greeks used therapeutic baths, for example, as did the Romans, the Chinese, the Japanese, and the Native Americans. Father Sebastian Kneipp brought it to the fore and popularised 'water-curing' in the 19th century. There are innumerable watering-places all over the world, and where would many of the novelists of the time have been without the recourse of their characters 'taking the waters'?

Why Use Hydrotherapy?

As people age, their joints stiffen and are often very painful to move, particularly if arthritis has become a factor. Therefore, regular exercise becomes important to keep the joints flexible and the muscles strong. No doubt many find the mere indulgence in exercise a boost to their feelings of wellbeing, largely due to endorphins. The endogenous morphine produced by the body is an anti-stress hormone that relieves pain naturally. It is believed that they are released by exercise of any kind, including sex and laughter - which can't be bad.

A gentle endorphin-releasing walk is often used to boost the heart-rate as a mild aerobic exercise - however this may become painful when pressure is applied to the weight-bearing joints - the hips, knees and ankles, and also the spine. This is clearly a major problem, and this is what hydrotherapy sets out to resolve.

The body weighs between 50 and 90% less when immersed in water to varying depths - shoulder-deep water supports the exerciser almost totally. Not only does this help remove the problem of impact discomfort, but also has the added benefit of allowing any required extra exertion to be carried out without overheating the body. There are studies that show that hydrotherapy assists the recuperation from injury, in some cases halving the time for recovery. A handy additional benefit of hydrotherapy sessions in swimming pools is that the exercise can be carried out in groups, and can therefore be quite convivial.

The simplest exercise is swimming, which in itself can be most enjoyable, both as muscle/joint developer and as a mental relaxation. More complicated exercises can be tailored to the requirements of the person receiving treatment.

The Role of the Physiotherapist

There are physiotherapists who specialise in taking groups in the pools attached to the hydrotherapy unit of hospitals or special centres. These pools are usually comfortably heated. Many therapists use specialised equipment such as flotation devices, or attachments that help to increase resistance, such as those that allow for stationary swimming against a gentle jet of water. There exist such things as underwater treadmills, and a personalised underwater walking or even jogging track is perfectly feasible.

Water Aerobics

Aquarobic classes can suit almost any level of fitness, from vigorous sessions in cooler pools to a more gentle version in warmer water.

These exercises can be done in public pools, but there are precautions to be observed. There is little point attempting exercises in the midst of an amateur water polo game, for example. The pool also needs to be accessible for the elderly, or those with disabilities.

A strange quirk of working out in water is the 'diving reflex'. With this, the heart actually increases in size by a small amount and is therefore able to pump more blood with each beat, decreasing blood pressure with a lowered pulse rate. The lungs also benefit from the aerobic effect.

Workouts in spas are possible - and very pleasurable indeed. It seems that a good soaking in the higher temperature of a spa lowers the internal body temperature ('core temperature'), promoting better sleep. This is a great stress reliever.

Safety Precautions

Naturally, consulting your doctor is a good start, especially for heart patients.

Be careful when exercising alone in water if you have health problems. A knowledge of cardio-vascular first aid will help in a group situation - instructors or group leaders will almost certainly possess this.

Grade your exercises: begin with short sessions and gradually build up time and intensity. The same general rules regarding this that apply for exercise on terra firma can be applied. Most importantly - don't overdo it. Too much, too soon has been the downfall of a great many exercise regimes.

Take in fluids¹. This applies especially if you are in a hot spa, which can act on the body like a sauna and put stress on the cardio-vascular system.

If you get pain from exercises, lessen intensity and duration but try not to give up, unless you feel you may have sustained an injury. Any reputable pool will have an instructor/adviser, and you should not feel bashful about approaching them. Remember, though, that you are making muscular effort, and some degree of mild discomfort is to be expected. Just don't overdo it!

Pregnancy is no bar to exercise and many pregnant women find it beneficial. But, as ever, check with your physiotherapist/instructor.

Sample exercises

Please note - these are guidelines only!

General common sense

• Use the same cycle for aquarobics as for land aerobics - warm up, build to your peak, maintain that peak, taper down, warm down.
• Move slowly and gently in the water, beginning and ending with easy exercises, and utilising the resistance of the water. Speed up only if you are comfortable.
• Keep a stable footing in the pool, and keep the body part being exercised submersed.
• You may like to begin by walking through the water - forwards and backwards with long strides, varying the depth of water. Always try to complete any joint movement, but don't force it through sudden pain.

Shoulders

• Reach out in front and slide hands to the side - later using flat palms to increase resistance.
• Fingertips on shoulders and circle elbows backwards.
• Shoulder rolls, forwards and backwards, beginning by moving them upwards.
• Move arms up and down against water resistance.

Arms

• Push out in all directions, even punching, or with fingers stretched upwards or downwards.
• Bend elbows, almost touching shoulders and straighten them.
• Turn and/or bend the wrists up and down.

Spine

• Feet apart, knees slightly bent, and twist from side to side. This will also benefit your waist.

Hips and knees

• Lift legs alternately out to the side and down again - this can be done in a seated position if preferred.
• From seated position, raise a foot to straighten the knee, hold leg straight, and then relax.

Legs

• Hold edge of pool and move legs as if riding a bicycle.
• Keep feet flat on bottom of pool, knees pressed outwards, and lunge from side to side.

Ankles

• Use a similar exercise to that for the wrist joints.