Open access journal publication:

West J, Dahlqvist Leinhard O, Romu T, Collins R, Garratt S, Bell JD, et al. (2016)
Feasibility of MR-Based Body Composition Analysis in Large Scale Population Studies.
PLoS ONE 11(9): e0163332. doi:10.1371/journal.pone.0163332

This resource can be downloaded or viewed using the link: AbdoBodyCompMethod.pdf

If you have wget available (typically on linux systems), then you can also obtain a copy using the command

 wget  -nd  biobank.ctsu.ox.ac.uk/ukb/ukb/docs/AbdoBodyCompMethod.pdf