Ben 10 The Rise of Hex

Play level 1 using the robot crab as much as possible since he's less likely to get hit (see my Unscathed solution). If you never get hit, you'll never have to worry about picking up a yellow health item. If you do get hit, it's probably best to restart unless you are close to the end. There's just too many places where it's hard not to collect a health pickup.

As for energy (green powerups), just make sure you wait for your energy bar to fill after each use before you progress through the level. Sometimes the robots will drop green powerups when they die, so make sure you don't charge forward into one of those and unexpectedly pick it up.