A load distribution harness for water based sports includes a stiffening shell provided with composite material. The stiffening shell has a support plate from fibre reinforced sheet material having thermoplastic matrix material with fibres embedded therein. The support plate is substantially C-shaped. The support plate extends continuously from a first end region that in use extends to a first end of the spreader bar, via a midsection that in use extends along the body of the user, preferably along the lumbar region of the user, to a second end region that in use extends to a second end of the spreader bar.