Today’s article “The Anterior Cruciate Ligament Can Become Hypertrophied in Response to Mechanical Loading A Magnetic Resonance Imaging Study in Elite Athletes” by Beaulieu et al. is from the University of Michigan.
Long answer short- maybe. If you can train to increase the cross-sectional area of your ACL, then the training likely has to start prior to age 12. There is nothing to suggest that there are particular exercises or sports that will increase the cross-sectional area of the ACL. The cross-sectional area of the ACL is important as it relates to the strength of the ligament.
This study is interesting as they looked at athletes- figure skaters and springboard divers- that load one knee more than the other as a part of their sport. They also included only athletes that started training before age 10 for female athletes and age 12 for males. The authors then measured the cross-sectional area of the ACLs of the athletes dominant and nondominant legs on MRI. The authors showed that only 63.5% of athletes showed a greater cross-sectional area in their dominant leg. However, the overall difference was significant with 4.9% difference in side to side cross-sectional area. As there is no noninvasive way to test the tensile strength of the ACLs, there is no way to test how clinically significant the 4.9% difference truly is.
This was an interesting article and hopefully we get future studies on the topic.