I'm a fan of creatine. From the research that I read, even though there's still lots more to learn, it is one of the best studied molecules in terms of what it Essential L Carnitine Optimal Health Systems Acetyl L Carnitine Vs L Carnitine Explained Australian Sports Nutrition A Meta Analysis of the Efficacy of L Carnitine L Acetyl Carnitine or N Acetyl Cysteine in Men With Idiopathic Asthenozoospermia Guangzhu Wei, Zhongbao Zhou, Yuanshan Cui, Yongjin Huang, Zijin Wan, Xuanyan Che, Yumeng Chai, Yong Zhang, 2021