Burnt umber studies

I started a study today for my next painting. Started with just a burnt umber sketch but the drawing grew so much i kept it at just burnt umber. looks pretty rad and i think ima do more of these.. this one only too me like 3-4 hours. also what i liked about it is thats a real study of anatomy. In other full color studies i see that i dont give much thought to the anatomy cuhz im so concentrated on color and temperature. trying to get the mixes right. So this was a faster so efficient i guess learning process. although the full color study is still essential and prob my next step i think this is another step added to my process.....