The CKMM gene codes for creatine kinase (CK), an enzyme involved in cellular energy production and in moving energy from mitochondria to muscle fibers in contracting muscle.
The TT genotype is considered unfavourable for strength-related physical activities. This is due to the low activity of CKMM in type II fast-twitch muscle fibers. Type II fast-twitch muscles are key in power-based training. Associations with the TT result include a very low activity of the CKMM gene and an undesirable effect on power-related athletic potential. If you carry the TT genotype in this gene, then it is recommended that you supplement and "add-in" creatine monohydrate: 2.5-5g per day.
CKMM plays an integral role in maintaining energy homeostasis by providing a steady supply of creatine phosphate. Creatine supplementation can help to regenerate ATP stores faster. Creatine monohydrate can be supplemented through a loading protocol. To start loading, take 0.3 grams per kilogram of body weight per day for 5–7 days, then follow with at least 0.03 g/kg/day either for three weeks (if cycling) or indefinitely (without additional loading phases). For an 82 kg person, this translates to 25 g/day during the loading phase and 2.5 g/day afterward. Higher doses (up to 10 g/day) may be beneficial for people with a high amount of muscle mass and high activity levels.