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 Underwater
Swimming - Effective Finning
There are several techniques for finning,
but the most common tend to be the standard 'flutter kick' and the aptly
named 'frog kick'. Both methods have their uses and you can adapt your
style depending on the type of diving you are engaged in.
The legs are kept straight (but can be slightly bent at the knee) and
move up and down in opposing directions. The forward thrust is
provided by the downward stroke of each fin and the upward stroke just
slips through the water - to get the fin ready for the next downward
stroke.
Your feet need to be kept at a constant distance from your body to
push the water backwards and to provide the forward thrust - avoiding
an otherwise ineffective bicycling type movement (with the legs
shuffling backwards and forwards).
Use your front thigh muscles to do most
of the work and use long strokes to maximise the time each fin spends
pushing you forwards.
The flutter kick is best used for speed
on the surface, to control ascents and descents, swimming in currents
and swimming mid-water (when clear of the bottom).
The main disadvantage of the flutter
kick is the fact that the 'flush' of water created with each stroke
can easily disturb the silt if close to the bottom and also the
delicate marine life.
The frog kick is the underwater
equivalent of the breast-stroke leg kick, with the legs moving inwards
and outwards in a circular motion. The forward thrust is provided by
the second half of the stroke, since the first half merely positions
the fins for the next thrusting kick.
Use the backs and insides of your thigh
muscles to do most of the work in a gentle relaxed manner.
The frog kick creates very little
downward 'flushing' and is best used when close to the bottom (silt),
close above the coral reef or delicate marine life, for general
cruising through the water and to rest the muscles.
Underwater
Swimming - Buoyancy Control
This is perhaps the most important
skill to master and ensures that you don't sink to the bottom and
damage the marine life or disturb the silt. Good buoyancy control is
also essential for many specific diving activities such as underwater
photography and wreck diving.
The Perk
Performance Buoyancy course is specifically aimed at fine-tuning
your buoyancy and establishing the correct amount of weight to use for
diving.
Often inexperienced divers are
over-weighted which means that they use excessive energy (and
breathing air) by constantly finning to stay 'neutral'. In fact, if
they stopped finning they would probably sink because they are using
too much lead and need to swim in an upwards direction to compensate
for the effects of being negatively buoyant. However, if they were
properly weighted they would probably find that previously they have
had a tendency to always be finning upwards and unnecessarily wasting
energy (and breathing air) to keep 'neutrally buoyant'.
Buoyancy checks at the surface are
conducted by holding a normal breath taken from the regulator and then
fully emptying the air from the BCD (and dry suit). If properly
weighted, you should float at eye level and start to sink only when
you exhale. Taking a further breath will cause you to rise back to the
surface, so it is important to breathe out when actually commencing
the descent.
It is important to remember that you
need to add air as you descend or go deeper and to dump air as you
ascend back towards the surface.
DON'T FIDDLE - only add air to
your BCD (or dry suit) when absolutely necessary and avoid the
temptation to keep adding or dumping air. Constantly fiddling creates
an 'elevator' effect which can potentially be dangerous. Remember that
there is a delay underwater for the effects of the additional air to
be realised. Air should only be added gradually in small amounts with
a deliberate pause after each inflation. Take a few breaths before
deciding whether you need to add any more air to the BCD (or dry
suit), otherwise you may be adding excessive air which will need to be
dumped.
The aim is to maintain the neutral
buoyancy that you started with at the surface when completing the
buoyancy check. Even when underwater, buoyancy should be controlled
through your breathing - taking a deep breath to raise above something
and then breathing out as you clear it. Never hold you breath, but
take deeper or shallower breaths to make fine adjustments to your
buoyancy (as with the underwater hovering skill) - rather than
constantly manipulating the mechanical inflator.
Summary - assuming that you plan
to swim at one depth, simply take a big breath to get over some
obstruction in your path and exhale fully to duck under something -
after all, divers were doing this long before BCDs were ever invented.
Diving
in Open Water during the winter months
Although the winter
months bring cooler water temperatures, the diving can still be
excellent for several reasons;
Some divers take time out and so the
dive sites are less crowded
- this means a more relaxed atmosphere and better visibility. The viz is also
better because the algae blooms will have died off leaving the water much
clearer, so you can maximise your enjoyment of the features underwater.
It is essential that
you wear a hood and gloves whilst diving at this time of year and
ideally you should be equipped with a dry suit. If you don't already
have your own suit, then please remember that you cannot hire a dry suit
from anywhere
unless you possess the relevant qualification which must be produced at
the time of hiring the equipment.
So why
not enrol on the
Dry Suit Specialty course? – an ideal way to
keep your diving warm and dry.
Other
options during the winter months
For those of you that
still aren’t tempted to get into the water – why not practice your dive
skills throughout the winter months in the warmth of the swimming pool.
If you haven’t been diving for a while, the
Scuba Review
programme is an excellent way to fine-tune those ‘rusty’ underwater
scuba skills in preparation for the warmer weather or a trip abroad.
Finally, for those of you that still can’t be tempted to get into the
water – why not invest in a first aid course? The
Emergency First
Response
course
prepares
you for the Rescue Diver programme, but it is
NOT only for scuba divers.
All our first aid
training programmes are approved by the
Health and Safety Executive
and are applicable to
all situations where people need assistance (e.g. family members in the
home or colleagues in the workplace). We even deliver the
Care
for Children
version of the course, which is brilliant for for parents
and anyone who comes into contact with children.
Just
Qualified or Need a Refresher?
What better way than to join
Frog Squad
at a dive site of your choice
and be led on a guided underwater tour. Accompanied by a dive
professional, you can be assured that you will be safely supervised and
can relax to enjoy the underwater experience.
 click
here
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