I use Optimal Amino to supplement my amino acids and efficiently boost protein. I also add 3 grams of HMB daily. The latter supports retaining muscle mass even without lots of exercise. If you are exercising, OA and HMB will improve your results in building muscle. You need to supplement D3/K2 as well for best results.
I just added the Dymatize hydrolyzed protein (chocolate flavor) from Amazon. It's 20 grams of protein per serving plus what ever protein is in the milk you mix with it. I use LactAid 2% or LactAid whole milk to mix with the Dymatize protein. 250 calories per serving with the 2%
We take “perfect aminos” use a protein bar (IQ) and eat venison sticks. With all that we get close to protein intake level needed, but it is a chore. Oh, and we do HIIT 3x a week. (We are over 70) Will look into HMB. Thanks.