SCUBACHAT
Buxton springs eternal
WHEN SCUBA DIVERS DO fundraisers , you normally expect the fundraising to be related to diving . Not in this case … 14 members of Buxton Sub Aqua Club , together with another nine friends and family , decided to raise funds for the RNLI in a rather untraditional way .
They took part in a sponsored abseiling event at Millers Dale , in the High Peak , back in June . It was a 90ft decent from the top of the bridge to the bottom .
The day went very well indeed , no one let themselves down .... well , they actually did , but only because they needed to get back to terra firma ! The group has so far managed to raise over £ 2,700 for a
charity that ’ s close to all UK divers ’ hearts . Collection is still ongoing at the moment . Ruth Carter , our Social Secretary and the organiser of this event , said : “ It was an amazing experience and I ’ m blown away by the support everyone has shown us . The most striking thing on the day was the teamwork and camaraderie shown by everyone who attended .
Some of the participants took it in their stride , others were more cautious and one or two took the opportunity to show off previously unknown skills . One even turned up ‘ dive ready ’ and did it in a drysuit , with a twinset on his back ! I ’ m incredibly proud of all the participants and would like to offer sincere thanks to them all .”
Ruth also offered her thanks to ‘ Abseil Derbyshire ’ for running the event in a safe and fun way .
Well done to Ruth and Ronan , Carl , Dawn and James , Jack and Rhiannon , Elizabeth and Mary , Nick and Nadine , Andy A , Collette , Helen , Karen , Richard P , Rogue and Ainslie , Joe and Izzy , Aaron , Reece and Daisy . Ages ranged from 10 to 70 plus ! ANDREW GREEN , Buxton SAC
Rotten inside
A MEMBER OF OUR BRANCH WAS DIVING ON TWIN SEVEN-LITRE cylinders when it was noticed there was gas leaking out , about a third of the way down the cylinder . Later , I removed the pillar valve and poured about a pint of water out of the cylinder . The condition inside was very poor , as you see in my photo . The interesting thing is that the cylinder was only just out of test , and about to be submitted for test . The owner of the cylinder is , generally speaking , very particular about looking after his equipment and cannot recall any instance that could have led to this failure . KEITH WHETTON
Editor ’ s response : Thanks for writing in , Keith . There ’ s two important messages here . First , keep up your maintenance schedule on cylinders , clearly a lot can happen between services . Second , your friend was fortunate that his fellow members were looking out for him , and took the trouble to investigate the problem . This is the overriding , often unstated benefit of club diving – we look after each other .
BECKYHITCHIN
Of cake and calories
How much energy do we burn while diving , and does it justify the traditional cake binge ? Becky Hitchin carries out a ( mostly ) unbiased review of the existing research
O ne of my biggest conundrums when diving is knowing exactly how many calories I ’ ve used during a dive - and most importantly , how many cakes I can eat guilt-free afterwards . I thought I would do a not-very-scientific reckoning to help all the readers happily indulge in appropriate amounts of Jaffa cakes , shortbread , chocolate cake , or whatever else is your particular fancy after a dip in cold waters . To start : kitting up . As we all know , as soon as you ’ ve got your drysuit on , basic activity becomes like weightlifting in a sauna . Saunas increase one ’ s calorie consumption to 1.5x that of sitting normally . Without finding an official calorie counter for the gymnastics involved in getting a drysuit on and wriggling into kit , I ’ m going to suggest calories burned during yoga to be a good comparison . I estimate 10 minutes kitting-up . That ’ s 70 calories . About 1.5 Jaffa cakes . Not bad before even getting in the water ! Of course , it often comes with a layer of sweat forming in your drysuit for added discomfort , and later evaporation . American diving researchers once estimated that an average shore-dive in temperate water burns as much as 600 calories per hour . I wanted to see where this figure came from , as it seems a lot for 60 minutes of floating around in the water waving at nudibranchs . So . There ’ s a number of reasons why diving in cold water will use energy . When our bodies are cold or in a cold
22 environment , they continue to work to maintain body temperature at 37 ° C . But in the higher densities of water , it ’ s generally said that heat is drawn off our bodies at least 25 times faster than in air . And unless you ’ re diving in a drysuit with dry gloves and a full-face mask , part of the body is always directly exposed to the water . In fact , the rate of loss of heat is proportional to the temperature difference between the points of contact , and heat loss in cold water can be 1,000 times greater than in air if we are actively swimming along .
It certainly feels like it after a while in very cold water . Maybe photographers really do have the best idea – stay as still as possible for the whole dive .
In the cold , our bodies undergo a process called vasoconstriction – where blood ( and heat ) is retained in the core . Eventually we start to shiver , a process to stay warm but which uses a lot of energy . Also , we breathe . It ’ s rather essential . Unless you ’ ve got the luxury of a rebreather , then the air we inhale is close to ambient temperature , and our lungs have to work to warm it . The deeper you dive , the more water pressure increases and a body needs to exert more effort to move or push through the water . Deeper dives use more calories . Working out the actual amount of heat loss anyone would undergo during a dive is subject to too many factors to think about here . Age , weight , distribution of body tissues , speed of swimming through the water ( again , photographers win out ), whether people are daft enough to go diving without gloves – or , for goodness ’ sake , hoods - on . On the physics side , discussion of heat transfer coefficients , turbulent flow , Reynolds numbers are bandied about . All lovely , but getting us away from the point of this article , which is cake . From a deep dive through the literature , PADI and others seem to agree on a loss of calories during a dive going upwards from 600 calories . I ’ m going to be bold and go for 800 to 1,000 , given the likelihood that a typical PADI dive isn ’ t in 8 ° C water , and for at least an hour . So , let ’ s add this up . 70 calories kitting up , let ’ s say 900 diving , and at least 70 calories de-kitting and warming back up . 1,040 calories . That ’ s 22 Jaffa cakes . With only 10 in a pack , that ’ s a great result . You could opt for eight shortbread cookies . Or two good sized pieces of sticky , gooey chocolate cake .
The conclusions from this extremely unreliable scientific study are important . It seems that actually I don ’ t eat enough Jaffa cakes after a dive . Undertaking this study has given me – and I hope all of you - the reassurance to go forth and clear the cake counters of cafes , pubs and all your local shops . �
Let them eat cake
HAVE READ WITH INTEREST BECKY Hitchin ’ s article on cake , I found myself asking the all-important question , what about the fry-up ? Cake is all very well for boat dives , but down here in Deepest Darkest Devon , Saturday morning shore dives are followed by a fry up at the Bay Tree in Babbacombe , Romany Jones ’ Cafe in Kingsteignton or the Haldon Cafe on the top of Haldon Hill on the way home .
How many Jaffa cakes are there to a fried egg ? If we go for poached , can we have an extra rasher of bacon ? Does the climb up from Beacon Cove allow for a slice of black pudding ? These important questions need answering . Exeter BSAC ’ s members dive off our beautiful beaches all year round ; we have members of a wide range of ages , weights , distribution of tissues , swimming speeds and even some who insist on wearing wetsuits in January . We would be an ideal test bed for this essential research .
Where can we apply for funding ? CHARLES SHELDRICK , Exeter BSAC
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