Initial review of Leaderfins Sports Mono Fins Advance.Last weekend i got the chance try out the monofins in the pool on Saturday and Sunday.
Fins are negative in bouyancy. they sink. but at depth this is good cause the knees tends to straighten out because of the weights. this help when doing the dophin stroke as modulation from the shoulders right until the feet get translated into power because of the whip like effect on the negative fins.
Putting on the fins is a hassel because of the design of the heel strap. i expected it to feel like putting on a fullfoot fins, but fullfoot fins the rubber at the heel is soft. this one is hard and is it not strechable. also the foot pocket gets smaller from back to front. this is suppose to hold the foot firmly so there is efficient energy transmission from foot to fins.so the trick is initialy put you foot as far as it will go then with the might of Zeus try to pull the straps behind the heel. when this is done automaticly the foot will get push to the front and fits snugly. then do it for the other feet. i do this by putting the legs together and lean them to one side to work on the straps.
The foot pocket fits just nice but on the first session i got blisters on toe, foot arch and the heel. i decide to wear a 3mm neoprane socks on the second session and this solve the blister problem.
This baby is FAST!!!
on a surface swim, the shockwave on the water starts from the head, not from the shoulders as with other fins.
initial stroke is difficult because the resistance impose on the fins. this is due to the large surface are and the weight of the fins. but when you get the momentum, the stroke is easy and relaxing. i really enjoy the fins in this phase cause there is simply no effort in driving them. and on top of it you are going really fast. i estimate that compare to the normal freediving fins that i use, for a given distance and at optimum performance, the monos cut time by 10-15% and effort 20-30%. but on the initial phase the freediving fins beats the monos because of their low inertia but when the monos are on high gear, it will leave the longfins behind.
on a dynamic run you will spend less energy, less time and operating at a higher speed for a given distance.
to drive the monos is difficult initialy because modulation of the body must start from the shoulders unlike other fins in which modulation from the waist is enought to drive them. also the legs must work and syncronise together
because i found out if 1 leg is out of sync, the slower leg will pull the fins and make it yaw to the inside and this will
change the direction in which the diver is going. and this is apparently the way to steer the fins but turning radius is big, almost plus 50% of a freediving fins. also during the stroke, power through both leghs must be evenly match if not the fins will skate to the direction of the weaker leg and this will cause a lost of momentum.
other than that, it is fairly easy to be learned and also the blades after 2 sessions in the water tends to get more flixible when dry. i guess its takes a bit of running in and to release the manufacturing stress from the blades.
so with the above findings i have concluded that i need about 2 months practice to master this fin, to get the technique right and to built the strenght and stamina do drive is properly.
also with the advantage of this fin i will try to set a new personal best in Dynamic Apnea of 75 meters from the current 50 meter record.
