Best Supplements to Prevent Age-Related Muscle Loss

Are there any studies in humans using Ursolic Acid to retain muscle mass in the elderly? It is supposed to be in apple skins, rosemary, plumes, etc.

I want to know the best way to get high-quality protein from whole FOOD, not from supplements.

What is the more beneficial- a regular collagen supplement or an amino acid supplement?

It would be helpful to have tips on how to better absorb protein. Older adults don't always benefit from the protein we eat. I'm 63 years old with a very healthy moderately-high-protein diet, plus I take 10 grams a day free form amino acids. My latest blood work showed low Total Protein, even though kidneys and liver seem to be healthy. I also take betaine HCl and enzymes at each meal.

When you state that "Plant-based foods can also provide protein and build muscle, although, individually they might not provide the optimum ratio of amino acids," you are dangerously close to repeating the now debunked myth that vegans and vegetarians must "combine" various proteins to get a "complete" protein profile. Credible studies exist on this topic:

https://nutritionfacts.org/2018/12/20/do-you-have-to-combine-plant-proteins-at-a-meal/
https://www.huffpost.com/entry/vegetarian-protein-complete-meat_n_5a90357ae4b01e9e56bb3224

I am a 69 year old man (6' 3", 185 lbs), and strive to eat a plant-based diet except for fish and occasional eggs. I consume 90-110 grams of protein a day; much of it from whole foods but with some augmentation from Garden of Life Organic Plant Based Protein (no financial interest). I also engage in relatively heavy weight training 3 days a week. I am easily able to maintain strength and considerable muscle mass. I consider the regimine a fountain of youth and highly recommend it to older folks.

as i understand it, it doesn't matter if you have all the essential amino acids at once as long as you get them all and a whole food plant-based diet provides them all. btw, and soy provides all the essential amino acids.

How about the bone broth protein powders?

Do you test protein powders that are sold directly from distributors like Usana, Shakeology, Shaklee, Plexus, Isagenix etc.?

For many years I have been making my breakfast smoothie with Natures Plus Unsweetened Gluten Free High Protein Energy Meal. All ingredients and digestive enzymes are listed. I am pre-diabetic but adding some frozen blueberries and small medium banana with CocoVia dark chocolate powder make a great shake. I purchase the powder from VitaCost.

I like to take Swanson Vitamin's organic pea protein powder along with its Green Max mixed in. They are inexpensive and don't taste bad or overly sweet like other brands. I use a small, inexpensive, high powered battery powered whisk from Amazon that takes double A batteries to whip it up quickly.

Here's a good resource to double check your protein powder.
https://www.cleanlabelproject.org/protein-powder/