Push on a tree or wall as hard as possible while using as little muscular tension/strain as possible. This will force you to maintain a clean connection from feet to palms. See the osensei photos for reference. Try to push yourself down. Notice how your shoulder collects and concentrates the stress so work on getting the force to 'bypass' the shoulder joint.
Find the feeling of the push going through you from palm to feet and remove the stress/strain from everywhere except that path through you.
Find that connected yet powerful feeling and do that while performing waza. You will be strong and 'relaxed'. Takes time and effort and guidance to really get beyond the very basic level.
At shodan one begins to see the futility of training the same way as before. It sucks but there is hope.