As I previously discussed, the impact small things can have in muay thai are pretty dramatic. I was reminded of this last class when another “that makes perfect sense, why did I not think of that?” moment came up.
The drill was punch –> knee –> elbow. Whatever knee you use (left or right), you follow it up with an elbow from the opposite side. Left knee, right elbow for example. I am going through the drill when the instructor comes up (kru was gone for this class) and suggests I try something. Instead of bringing my leg back to where it came from before the knee (typically this would be behind you), throw the knee and then leave it forward, but step off to the side of your partner/opponent. I didn't even need him to explain why after I saw him demonstrate it as it was perfectly clear: efficiency.
Measure from your shoulder to your elbow, and then measure from your hip to your knee. For most folks, the hip to knee measurement is going to be longer. This means that your range for a knee vs your range for an elbow are going to be pretty different (you need to be closer for an elbow strike). If your combo is knee –> elbow, and you are putting your foot back behind you after your knee, you are putting yourself in a spot where now you need to close that distance between you and your partner/opponent before throwing the elbow. Depending on the situation, this leaves you open to attack and allows your opponent to recover/reset. At the minimum, it is more energy you are now having to use to close that gap for your elbow.
By leaving your foot forward and stepping off to the side of your partner/opponent, you are now almost chest to chest with them. You can go directly from your knee strike to your elbow strike without having to re-position yourself or close any distance. You've gone from a “boom... step step... boom” to “boom... boom” :).