Speed sailing on flatwater a seat harness is great.
But in open sea( chop and swell) a waist harness is a must too absorb the chop, as a seat harness is too locked in, wearing a seat harness is asking for a catapult. This is why pwa riders use them
But there's always exceptions for some people

i sail slalom kit in choppy, rough water, often for over an hour non-stop (save for crashed gybes)...

a game changer for me was the Liberty XO (Crossover) harness (which, by the way, many pros use; even if their aggregated time on the water on competition day may be an hour or less, they do train for longer and harder than most of us ride). it is a low waist harness with a butt pad, so a cross between a seat and a waist harness; but unlike a traditional seat harness, it doesn't lock in your hips and legs. Starboard/Drake also make a version of the same design, but it's a bit stiffer than the original Liberty (which has a soft carbon shell). please note the sizing, as it runs large (so if you're typically an L, you'll likely be an M in this harness). it's important your bar pad is long enough to almost have overlap with the harness ends.

before this harness, after an hour of riding i was ready to scream. now i can sail for longer with less discomfort, and this has actually helped my results. in more than a few sessions, the conditions haven't really lined up until well into the second hour of riding when in my older waist and seat harnesses i would have been hurting (if not off the water altogether); having energy in reserve to push and get a decent result at that stage of a session was priceless.

kato said..
Distance. Seat harness with a sliding bar.

I have really wide harness lines and I can move along them if necessary. Does this give anything like a sliding bar affect?

sboardcrazy said..

kato said..
Distance. Seat harness with a sliding bar.

I have really wide harness lines and I can move along them if necessary. Does this give anything like a sliding bar affect?

No. What they said ^^^^^

WindFlyer said..
i sail slalom kit in choppy, rough water, often for over an hour non-stop (save for crashed gybes).

a game changer for me was the Liberty XO (Crossover) harness

Ive decided to go with the liberty xo option.
The wait time is long and it's very pricey, but I think it will do the trick.

I realised almost all my troubles are in moderate conditions when I'm really hiked out and back, while going across the wind a and I'm really pushing with straight legs and arms to rail/ fly the board for a long runs. I have no issues with the waist harness when fully powered with a sunken stance, when going off the wind, or on a multi fin board in the ocean.

So in moderate conditions, Transferring some of that load from the sides of my back to the seat flap of the xo seems like a solution. One which won't kill control when long distance gps blasting in the ocean across waves, like a seat harness might.

shannon19 said..
Where did you buy it from?

libertywinds.jp/products/harness/index2023.html

Placed an order by emailing these guys^

I think there are few untested assumptions about seat harnesses here. I always sail seat harness. 100+km days in rough seas with no problem. If you have any kind of lower back problem (which I do) they are much to be preferred. I can't think of any time when I was out blasting in 1-2 metre swells with chop on top where the seast harness prevented adequate control.

mr love said..
The reason most speed sailors wear a seat harness is that we are all old farts with stuffed backs...

Some more than than others