Howatson, Hoad, Goodall, Tallent, Bell and French (2012), in a double-blind placebo controlled study, demonstrated that exercise-induced muscle damage (EIMD) is reduced when a supplement of 2:1:1 leucine: isoleucine: valine was utilized in combination with the training protocol of successive drop-jumps. Previously, Shimomura, Inaguma, Watanabe, Yamamoto, Muramatsu, Bajotto, Sato, et al. (2010) found similar results with BCAA supplementation utilizing a squat protocol and a drink supplement consisting of 2.3:1.2:1.2 leucine: isoleucine: valine in combination with green tea powder (Read more about BCAA + Caffeine Here).
Interestingly, both studies utilized branched-chain amino acid supplement and an EIMD protocol that recruited primarily type II, type IIx and type IIa muscle fiber types. Knechtle, Knechtle, Mrazek, Senn, Rosemann, Imoberdorf, and Ballmer (2011) tested the effect of an amino acid supplement (not just BCAA) on 100km ultra-runners in another randomized controlled trial. They found no effect on the reduction of creatine kinase (CK) markers (all studies tested for CK) or reduction of EIMD.
Further research is needed to determine whether BCAA supplementation is effective for EIMD in oxidative fiber types (as opposed to a general amino acid supplement) or only for EIMD induced via stretch-shortening cycles and/or anaerobic training (i.e. squats).
However, power athletes and those who use training protocol that requires stretch-shortening cycles and sub-maximal and maximal loads for anaerobic strength training, would specifically benefit from BCAA supplementation before the workout, particularly on leg days which tend to be higher in EIMD than upper body days.
I would also recommend a combination protein-carbohydrate supplement post workout and ingestion of carbohydrate and protein every 2 to 4 hours after the workout over the course of the day for optimal recovery. A good carbohydrate to protein ratio for post-workout recovery is on the order of 2:1 to 3:1 carbohydrate: protein ratio. These ratios will vary by supplement brand. If you have time to make a good meal, it is always better to eat real food when possible.