Any serious student of Yoga knows what the Pancha Koshas i.e. Five Sheaths mean. Please study them if you need to.
It is interesting that the Energy Sheath is more powerful than the Body Sheath. Thus, if one gets hold of Energy Sheath, one can get Bodily Health and Fitness easier. And, so on.
But, to get hold of Energy Sheath, one has to work on Body Sheath to some extent, and climb to the Energy Sheath. This is like the fact that one can observe more from the second floor what is happening on the first floor and also direct the first floor. But, to climb to the second floor, one has to somehow cross the first floor. Get it?
Thus, while working at one level in Yoga Practice, one should try to climb to the next higher level from time to time, and use it to improve the previous practice! Only when you escape the Material, you can work on the Material the best!