The amounts of protein that one should eat does seem to be somewhat controversial.
My feeling is that high protein speeds recovery and spares lean muscle mass. Again, I realize I am somewhat on the high end with the amount of protein I eat and am not recommneding this for everyone.
When doing large volumes of exercise or high intensity sessions it is my understanding that we must eat .7 grams of protein per pound of LBM (lean body mass) just to avoid catabolic muscle wasting. I am under the impression that 1.0 to 1.5 grams per pound is best for building/rebuilding lean mass. I also know that most folks in triathlon/running/cycling probably don't come close to this amount.
I do not find it difficult to eat 250 grams of protein if I look for it.
In order of ease of use by the body and amino acid profiles I ilke to eat: Non fat cottage cheese (70 grams of protein in a large tub), white turkey breast, fish (tuna, halibut, salmon), skinless chicken breast, lean red meat and egg whites. Red meat has a great amino acid profile but a bit more saturated fat. Egg whites are great protein but are harder for the body to assimilate. I have read that only 80% of egg white protein is digested. That is still a good source without the yolk. I also get protein from non fat yogurt, tofu, lentils, milk, cashews and almonds.
Sometimes I will supplement powders if I am not able to get as much ingested as I wanted that day.
Is it possible to consume too much protein in a meal or a day? In my opinion, and the opinion of some researchers, the amount of protein you can consume in a meal or in a day is trivial compared to what the body is able to absorb. The amount ingested and it's crude form can affect the time needed to absorb the protein. It will absorb it unless there is enzyme difficiency or other problems present. There was a time when it was thought that too much protein could damage kidney or liver function. There is a lack of evidence for this thought today. Studies show that extraordinarily large amount of protein do not harm those organs. However if you have pre-existing problems in the liver or kidneys they can be exacerbated. Our ability to digest protein is dependent on our intestinal health and motility, or how quickly our food moves through us. The faster it moves, the less we get out of it and we waste nutrients. For healthy folks like us, motility depends on physical and mental stress as well as foods and chemicals we ingest. Cheese slows motility and caffeine speeds it up. A quad espresso before a protein shake is not a wise thing. We want to spare muscle protein and the catabolic effects of hard excercise. I feel we do this by loading high quality protein at the right times of day and in the right amounts.
Kevin Purcell, D.C., is a USAT Level 1 certified coach for Elite and Age Group triathletes who compete at both Ironman and short course distances. Coach KP has completed 10 Ironmans and qualified for the 2003 Hawaii Ironman Triathlon World Championships. Dr. Purcell practices Chiropractic with an emphasis on sports medicine in San Diego, California and can be reached at firstname.lastname@example.org.