Is submuscular or intramuscular the best for me as I am very active and exercise a lot?

You should consult in person with an expert in this surgery to determine an appropriate size for your body dimensions.   All of the patients for whom I perform butt implants are skinny or muscular with very low body fat.  I place implants within the muscle to minimize being able to feel or see the implants. This creates a much more natural result. The intramuscular placement also reduces the risk for capsular contracture and sciatic nerve damage.  Exercise can be resumed between 6 and 8 weeks following butt implant surgery.

Although some individuals, including surgeons, use the terms interchangeably, technically buttock implants are most appropriately placed within the muscle (i.e. “intramuscular”). If they are placed completely submuscular there would be a very high risk of the surgical dissection and/or the implant itself damaging and/or impinging on the sciatic nerve as well as other important large blood vessels deep within the buttock  compartment.  
Because an extremely few number of board-certified plastic surgeons perform this surgery, make sure you select someone that is reputable and performs this surgery on a regular basis and is a respected specialist in buttock implants surgery. There is little room for error. Revision surgery is very complex and can be quite expensive. However if done correctly by a true specialist, the procedure is relatively safe and the results can be very rewarding and much more permanent compared to fat transfer BBL. Glad to help  

Dear Adelealm,
I avoid butt implants bacause of high risk of complications and low patient satisfaction rate. If you are considering a surgery, I would suggest you to consult a board-certified plastic surgeon. Only after a thorough examination you will get more information and recommendations.
Daniel Barrett, MD

Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

If done properly, subfacial may be the best way to go for you to avoid complications and still have a beautiful, long lasting result. Please be sure to choose a board-certified plastic surgeon who specializes in this procedure and is well known for their work in the medical community.

Sub muscular is a term often used with breast implants because they are truly placed below the pectoralis muscle. Sub muscular in regards to gluteal implants isn’t really appropriate and isn’t really done. Anatomically this is not a desirable place to be putting implants.Most providers are probably referring to intramuscular but perhaps in a deep plane.gluteal implants are tricky and I suggest finding the providers who have extensive amounts of experience with this procedure if you choose to go down this route. gluteal implants should be thought of as some thing once in a lifetime and isn’t something where you can just take them out if you don’t like them. Removing gluteal implants can lead to deformities that were not present before the initial procedure.Proceed with caution.Best, Mats Hagstrom MD