After executing the Thunder Roar Zen so many times, Lou Cheng was rather drained. Of course, no issues with his physical stamina, just that his mental stamina was reaching its limits.
To tighten and pressurize certain muscles and to maintain control over them until reaching the enemy and exploding in full force was something that took up a lot of energy. Not to mention that during this process, the fighter still had to punch and attack.
With this battle, Lou Cheng estimated that the maximum number of times he could execute the Thunder Roar Zen was ten consecutive times. Anymore he would have physical strength but no mental power to do so anymore.
It was the reason why he did not try to entice Yan Zheke to continue to stay in the locker room and whisper sweet nothings. Instead, he took her suggestion to return early, take a nap and do some revision with her in the evening!