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Fins
1-24-03
Okay, here is a topic that I know will rile some folks up. All I ask though,
is before you swear by your fin, make sure you know how to do a
straight-legged, deep (your two feet end up very wide apart), slow, ankle
snapping kick - and try both kinds of fins against someone of similar
ability. Read the following and you will see why I say this. It has become
silly at this point at how many times split fin, force fin, etc divers who
absolutely swear by their fins find out in 3 minutes that their fins do not
hold up when power is needed.
Public safety Divers need power -NOT speed. We need to hold our own and move
forward in currents. We need to be able to make headway when carrying
something bulky, or when assisting another diver. "flimsy fins" are designed
for speed. We are swimming in full gear, not swimming on a swim team in
bathing suits. Gear = bulk = drag = need power.
Also try the following. Stand in chest deep water. Have someone stand in
front of you and slowly wave a find up and down a few feet from you. Do you
feel water movement on both the upward and downward strokes? If you only
feel it on the latter, then literally half your leg movements are wasted
effort. How far can you get from the person before you stop feeling water
movement? The further means the more water means the more power.
Here we go.
The question we received, from a well informed diver was: "To begin with,
I'd be interested in hearing your point of view regarding
the fins you encourage. I've used Force Fins for years and think they
are very efficient, stream lined and easy to don/doff. "
The question came after we watched three divers on his team who had bunny
ear and split fins experience breathing rates over 25 bpm with a simple
surface swim in full gear. All three divers were in good shape. The problem
was soley because of the fins.
Here's our response:
One of our HQ instructors is just starting to write a small piece on that
(Brian Nylander). I will ask him to send it to you when he's done. Force Fin
has done one helluva marketing job. Force Fins must have learned from Harley
Davidson. I have yet to meet a military diver who diver who wears them for
military diving. I know that the Canadian Navy tested them and ranked them
on the bottom of the fins they tested. Dr. Glen Egstrom of UCL tested them
and ranked them the lowest in regards to his kinesiology work. Our personal
trials and watching increasing number of students with Force Fins, Split
Fins, Bunny Ear fins...... repeatedly and consistently show that they do not
allow for a powerful kick - divers get very tired on the surface when moving
from one place to another and in a current they are in big trouble.
Just watch divers wearing Scuba Pro jet fins kicking their way easily over
the gunnel of an inflatable, and then watch the same divers do the same
skill with Force, Split, or other flimsy fins. Diver's knees bend with these
fins. Bent knees means you're not using your strongest leg muscles. So many
divers swear by them. Then all we do is do the push o war game. Two divers
face eachother with mask fins snorkel on the surface. They clasp hands, face
in water, and then push each other. Who ever pushes the other diver
backwards x distance wins. Pair up two divers who know how to kick, one with
Jet Fins and one with the "flimsier" fin and see what happens. Don't take
our word for it. Try it. For every one straight legged, deep, slow Jet Fin
kick, the other diver will be making two or more kicks with the flimsier
fins - So far more effort with no gain - or even less gain.
I watched two divers on a sport diver in Mexico. Both were in better
physical shape than I was - they were mountain Bikers and one was a dive
instructor. I stayed behind them. We moved at the exact same speed, and they
made two kicks for every one of mine (they were both taller than me also).
They both used more air. They both became more fatigued. One other guy, I
ended up pulling another guy by the tank valve to get him up current to the
boat. He had a new Mares flimsy fin. When we switched fins later after he
rested on the boat and played the push game he beat me. When I took my fins
back and we played again I pushed him back with almost no effort. I watched
another pair of divers who recently switched to split fins who could not
figure out why they could not longer get themslves into the little chase
boat.
Cheers,
AZ
Andrea Zaferes
Lifeguard Systems & RIPTIDE
1-24-03
I agree I have used the USD super rocket fin since 1968 and I do swear by them and
other of the same design. We need power not speed!! Right on the money!
Ronny Phillips
Dive Master
Galveston (TX) Police Department
Marine/Dive Team
1-24-03
Another great advantage to Scuba Prof Jets is their weight. Having a
negatively buoyant fin is an asset for bottom dwelling, black water
searches.
1-24-03
I have tried most of the new fins now. I have decided I like some of htem but
only for specific purposes. The split fins are OK but I canot truly feel
enough difference in the to justify switching to them. They do not support a
hard power kick but do offer an easy stroke if you are going with a current.
As long as you do not need to hold a position against a current, they are
great.
The various new shaped fins and fins with wierd slots and slits are mostly
like novelty fishing lures. They more fishermen than fish. They do not have
power or provide much thrust with a minimal kick.
All this said, I found the ScubaPro Jet fins to be the best fin for me for
about 25 years and had the same pair for that long. As I got older and the
body more abused, the short foot pocket of the Jet fin begin to cause cramps
in the bottoms of my feet.
I switched to a plain, still generic paddle fin and was surprised at how much
more comfortable they were. At one time we had bought the Dacor Hurricane fin
and they casued more leg cramps that we could stand. They were way too stiff.
Now, after experimenting with the various fins, I have decided that my
favorite all around fin is a Volo hinge fin. I get power, manuverability and
speed and I fel like I used a bit less energy that I do when I use the paddle
fin. However, when I am spearfishing, or taking photos in a strong current, I
use a paddle fin. They feel to me, like they give me more power and stability
in porportion to the effort I expend. So if I need to go against the current
to get a picture or I need to fight a 45 lb Ling, I am more comfortable with
the paddle fin.
Notice, this is all recreational diving ...
When we do PSD work, we use either a paddle fin or a jet fin. We consistantly
get power for work with these fins and almost as important, we can buy two or
three of these for the same price a single pair of the fancy fins costs.
Thanks, AZ - It is nice to be able to talk about the fun part of diving every
now and them.
Mark Phillips
PSDA
1-24-03
In our research to evaluate swim fins for surface swimmer operations we tested a number
of different types of fins. The selection of fins included Force Fins (Original,
Pro, and Rip Force), Scubapro Jet fins, Aqualung Rockets, and numerous styles of short
"surf" style fins (originally designed for bodyboarding but now popular with
swift-water rescue practitioners. The results - while arguably subjective - were
rather interesting.
We conducted the tests in the following way. After swimming 200-300 yards
"slick" as a warm-up we took a breather, donned the fins to be tested, swam a
50m freestyle lap in a 25m pool at a "moderate" pace, and recorded the time it
took to complete the lap. Each tester then recorded the subjective "feel"
of the fin (i.e. their overall impression). After a short break the tester then
submerged and swam one "streamlined" (arms extended in front of body, kicking
with a relaxed pace) 25m length underwater without taking a breath. Once again times
and "feel" were recorded. Different testers tried the fins in different orders
and some fins that did well in the beginning were tested again at the end to try and rule
out fatigue.
Again, the results were far from objective and any scientist worth his salt would throw
out the whole process but it answered a lot of my questions.
The Results:
Perhaps not so unexpectedly, price had little to do with performance (although the
expensive fins were generally more comfortable to the bare foot).
All three types of force fins "flopped" out of the water during surface
freestyle swimming - losing half the stroke and disrupting the swimmer's rhythm (I readily
admit that I may not be kicking the "right" way according to the manufacturer.
Be that as it may I'm satisfied with the way I kick... it works well for me.
Times were uniformly slower than with the fins that stayed in the water for the
whole stroke.
During the underwater test the fins felt like they produced less propulsion The
manufacturer says this is not actually the case - it only feels that way but the times
were slower and the kick count (number of kicks per length) was higher.
One of the high end surf fins performed similarly even though it was the most expensive of
that style fin at $90.00 (versus a far better performing - though uncomfortable - $15.00
fin) and advertised as the result of advanced computer design.
I for one was surprised (and very disappointed) by the results. I WANTED the Force
Fins to work better. I tried to MAKE them work better. Unfortunately I
couldn't.
Another interesting result - Large Jetfins and Rockets performed very similarly to the
smaller surf fins with respect to time per lap. Remember we tried to keep the
percieved EFFORT the same (difficult to do I know). There was a marked difference in
HOW we kicked with the different fins (slow powerful kicks with the larger SCUBA fins and
quicker short kicks with the smaller fins) but the overall effort and times were
remarkably similar.
It's my guess that the differences will show up when wearing rescue equipment and dragging
a load (that's the next test we have to set up). I expect we'll see an untapped
"reserve" of power in the larger fins that can be used for short bursts (albeit
with increased fatigue). It will be interesting to see how it plays out.
The only other difference was that, not suprisingly, leg fatigue was higher with the
larger fins (respiratory effort was the same but the legs felt the larger fins more).
Anyway, that was our experience. Please don't hammer me on the "scientific
validity" of the test. I realize there were multiple uncontrolled variables and
it won't hold up to peer review - I concede the point.
Stay safe,
Jon Taylor
Virginia Beach Fire Department
1-27-03
I use an old but tried and true set of fins: White Stag (anyone remember
these?). They have been slightly modified by replacing the rubber fin strap
with a stainless steel spring system very similar to a fin developed in the
'80's. They are easy to put on and take off...actually, hands free if I
want, I just step into the foot pocket and roll the spring up with my other
foot. Same goes for taking them off. You dry suiters should consider the
spring system too. I will cry a pool of tears when they finally go to the
happy hunting ground as the fins are no longer in production. I've had them
for a very long time, maybe 20 years, and 90 % of my diving is Southern
California beach diving in 1' to 6' surf (if it's much bigger it's not much
fun!). Obviously, I haven't lost them yet. Lots of power but smooth build up
when initiating a starting kick cycle. They are negatively buoyant in fresh
and salt water.
I also teach SCUBA at times for a large chain retail sport equipment store.
With the new composite fins, the old method of "keep your legs relatively
straight" doesn't work. The extended bottom of the foot pocket and ridgidity
of the non-vented blades seem to change the leverage point of the fin. They
are definately harder to move. Additionally, unless the fin is really
cranked on tight, the surf can work it off much more frequently than, say, a
Scubapro jet. I guess that's one good reason for the fact that they will be
neutral in fresh water but float in salt water...a chance for recovery.
1-27-03
Hey, I'm not here to run down anybody's fin or anything like that, so don't start
shooting. As far as I'm concerned, it is a good deal that we have so much variety
now available for a diver to choose from. We all have our personal preferences and a
fin that works well in one application or for one person will not necessarily work for
another. Before you outright dismiss Force Fins, however, hear me out. By the
way, there is no scientific testing involved with this, just my own experience and
observations.
Shortly after I began diving, a friend who at the time owned a local dive shop, loaned me
a pair of Force Fins that he wanted me to try. As I recall, were new on the market.
I gave them a spin in the pool, but didn't think much of them. They didn't look
like anything that I ever saw Mike Nelson or Jacques Cousteau ever wear. The cool
factor was way down. I returned them to the dive shop and thanked the proprietor,
telling him I wasn't interested.
Over the past few years, out of curiosity more than anything else, I have tried out
several different varieties of the new split fins. Didn't care much for any of them
either, too much fin wobble to suit me. But, I see a lot of divers using these fins.
I started diving in 1977, and from the very get go I suffered severe foot cramps. I
used Scubapro Jetfins, Voit Duck Feet, Farallon Fins, Scubapro Gorilla Fins, and several
others, all with the same result. About halfway through my first dive of the day, my
feet would start cramping. These cramps would remain with me through the duration of
the diving day and most times for several days thereafter. Were it not for the fact
that I loved diving so much, I would probably have chucked the whole scene as an
experience gone awry.
I used to beg my kids to rub my feet (of course, clean socks were involved) and initially
they were willing to do so. However, they soon realized that I was like an addict,
the more they rubbed, the more I wanted. Being astute kids they soon figured out
that I could be bribed to pay for these services. Their charges went form one cent,
to five cents, to ten cents, to a quarter per minute. Not being wealthy, there was
no way that I could afford to pay any more. They eventually each profited enough from my
aching feet to pay for their college educations and put a down payment on their
first homes. Their finances secure, they no longer found it necessary to continue in
such menial employment. My wife was sympathetic to a point, but after a brief time
she too abandoned me in favor of some household task that just couldn't wait. So,
there I was left sitting in front of the TV set night after night rubbing my own aching
"dogs".
Eventually, the pain in my feet became constant as opposed to just from diving. It
got so bad that I went to my doctor who referred me to a podiatrist. The diagnosis
was "plantar fasciatus" (I'm not at all sure about the spelling). I was
instructed in how to tape my feet and prescribed orthotic insoles to wear in my shoes
which provided a lot of relief when I was walking. When I told the podiatrist about
the foot cramps from diving, he suggested placing orthodic insoles inside my dive booties
to provide support to my feet while diving, standing on a boat, beach, etc. They did
help somewhat, but not entirely.
One day after a day of diving, I hobbled into another dive shop, owned by another friend
of mine. The proprietor asked why I was limping and gave him a Reader's Digest
version of my foot problems. He asked if I had ever tried an open toed fin, and I
said, "Huh?" He went into the back room of the shop and emerged with a
pair of Force Fins. I told him that had tried them in a pool years ago and
wasn't impressed. He insisted that I take them and try them in open water. So,
I reluctantly did. They still didn't look "cool" to me, but I was amazed
at the result that I had while diving. No more foot cramps.
I was concerned that these floppy type "Original Force Fins" would not be
adequate for the loads that I needed to be able to push while diving for our Search and
Rescue team, and I expressed this to the dive shop proprietor at the time I returned the
fins to him. "No problem," he said and disappeared into the back room
where he appeared with a pair of what he called "Extra Force Fins". Man
were these things weird looking: something right out of Star Trek Underwater. They
were long and narrow with these long plastic "teeth" that protruded from the top
of the fin and could be rotated- presumably to provide more or less power. Again, he
insisted that I try them. Bottom line is that I ended up buying both pair of fins.
I use the floppy fins on vacation in the Carribean or Hawaii, etc. I use the
longer, stiffer, "Extra" model for SAR (PSD) diving, and I find that they have
plenty of oomph.
I guess that my message is, if you are having the kind of foot problems that I was and
haven't gotten any relief, you might want to at least consider giving the Force Fins a
try. The "Extra" model is not inexpensive: retailing at around $300.00 -
the price of power plus pain relief!
1-28-03
Alrighty,
Public safety Divers need power -NOT speed. We need to hold our own and
move
forward in currents.
Do you dive off line in currents? I have read your book and find it
interesting the section on drift diving...Ever been to River Rescue in South
Bend? Ever see what collects at bridges and road sides both naturally and
via hillbilly? I ain't "drift diving" into the unkown.
We need to be able to make headway when carrying
something bulky, or when assisting another diver. "flimsy fins" are
designed
for speed. We are swimming in full gear, not swimming on a swim team in
bathing suits. Gear = bulk = drag = need power.
Do you also need power when trying to reach the paniced diver at the
surface? The powerful fins give speed at such a high cost is the power fin
diver in any condition to aid a victim once he(she) gets there? One paniced
diver, one exhausted diver...hmm
Maybe an analogy will help. 3 cops are sitting down at a table. 2 of those
are discussing their exercise routine. One promotes endurance training,
quoting that in any fight if it lasts more than one minute both parties are
usually spent. (unless one is doped up!) So high rep-low weight, distance
running etc. is where its at. The other cop, who is into low rep-high
weight, says he will be able to end the fight before the minute is up
because he is more powerful than 99% of the violators out there. The third
cop is sitting there eating a donut graciously provided by the deputy
prosecutor who used to be a defense lawyer.
HELLO, does anyone see my point?
I've tried the bunny ears once. not enough to form an opinion. I've been
using force fins for a year now. I have outswam better divers with jet fins
at a lower physical cost several times. I'll try the push o war (in full
gear at depth) next this week. I'll let you know how it turns out.
Robert Duff
Indiana Conservation Officer
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