The two photos below are my "before" with red helmet and "after" photos with white helmet.
Move my saddle 10mm higher - so now I am 83 cm from crank head to middle of saddle compared to an inside leg of 90 cm (that is a stunning 0.92 ratio compared to the text book ratio (LeMond Ratio) of 0.883. Reason: opens up hip flexors
Move my cleats right to the back of the shoes: Reason, I have strong quads and should be using them to cycle and save my calves for the running.
Move my saddle even further forward by 10 mm. So now my knees are really over my toes in the classic 3 -9 oclock position. Reason: opens up hip flexors
Move my pads up by 20 mm (not the stem, just the pad stack). Reason: open up body for breathing and get body straighter
Move my hands higher in front of my face more: reason aerodynamics: but makes it more difficult to see the road
Move my head lower: reason Aerodynamics but it is slightly uncomfortable
Move my arms more forward to strighten out my body: Reason Aerodynamics
Change Helmet to Giro Aerohead.
Total saving about 15 watts. https://www.boardmanbikes.com/gb_en/performance-centre/