Came across this the other day, and while you'd have to be either insane or a pro athlete who needs to pack on muscle or cut weight for competition, it's a pretty interesting read and would be of interest to anyone wanting to pack on some lean muscle. Especially any hard gainers out there who think they've "tried everything" and just can't put on muscle.
His diet is not strictly primal, but seems to mostly fall in that category as it's only really meat, veggies, bread, protein powder and a few supplements. So you should be able to replace the bread with primal carb sources, etc. for similar results should you choose to.
Obviously, this would be more manageable for most over a longer period of time, or a lower goal of muscle mass gain in the 28 day period. But even 10lbs of muscle in for weeks would be a good result for most.
The free pdf includes a breakdown of his diet and training for the 5 weeks, both of which are pretty in depth and worth a look if adding muscle is one of your goals.
I recently agreed to try a crazy experiment in the name of science and conquering boredom. The specifics: Gain as much weight as possible in 4 weeks, lose as much weight as possible in 5 days, and try to gain it all back in 24 hours. Click here read the Introduction.
A quick, easily-digestible summary of what happened in my 34-day extreme weight manipulation experiment. I also introduce my coaches, Martin Rooney and Dr. John Berardi. Click here to get all the details.
If you're interested in my (very) occasional updates on how I'm working out and what I'm eating click here.