As you all know, one of my favorite parts of doing this blog is the constant, unyielding, uncompromising feedback I get from readers. When I make a mistake, or overlook a crucial piece of a puzzle, someone tells me where I went wrong or provides that missing piece. For today’s edition of Dear Mark , I’ll be addressing two emails from readers who took me to task for things I missed on this week’s posts.
The first comes from Simon, who had a great suggestion for increasing neuroplasticity. The second comes from Jen, who highlighted a new study shedding light on the effect of extra protein on muscle gains.
I really liked your post on neuroplasticity, but I think you may have missed a big one: socializing!
This makes sense on an intuitive level. When you’re alone, you control the environmental inputs. You can expose yourself to novel situations and inputs, but you’re the primary arbiter. It’s a curated experience.
Adding one, two, or several more big-brained hominids (or an entire party full of them) who can think and talk for themselves catapults you into new strata of novelty. Spending time with other members of the most intelligent species on earth can be intense.
You’re not reacting to a static novelty input, like a new route home or a beautiful piece of art you’ve never seen before. You’re responding to another living, breathing mind who challenges you.
You’re not analyzing a character in a novel or movie. You have to exercise empathy, to place yourself in another person’s shoes (and head) to maintain real communication.
Keeping up with other people requires mental agility. I’m thinking that has to induce some profound neuroplasticity. So, what does the research say?
We know that social isolation turns off genes related to neuroplasticity  in the prefrontal cortex and hippocampus—at least in rodents.
Chronic social isolation also causes depressive-like symptoms while reducing neuroplasticity.
We’ve all heard of oxytocin, the “love” hormone. Perhaps a more accurate description is “socializing” hormone. Hanging out with other people increases secretion of oxytocin partially to increase pleasure and promote socializing, actually triggering the release of endogenous cannabinoids . A good laugh with friends really can leave us feeling high as a kite.
But oxytocin also helps us tune into the emotional cues and body language others give off , determine friend from foe, and respond accordingly. In animals, it has also been shown to mediate certain types of neuroplasticity, particularly in instances of sensory deprivation . It’s almost like the body “knows” that socializing with other humans requires a nimble mind able to make new connections in the brain.
Great suggestion, Simon!
Any thoughts on this paper? Made me think of your post from the other day on lowering protein or not.
Here’s the paper . They took weightlifting novices—people who hadn’t lifted regularly for the past 2 years but who did regularly play team sports—split them up into a high-protein group (1.8 g/kg per day) and a normal-protein group (0.85 g/kg per day), and placed them on identical training regimens for 8 weeks.
They did bench press, shoulder press, lying shoulder extensions, seated rows, lat pull downs, and bicep hammer curls. They totally skipped leg day, in other words.
To hit 1.8 g/kg protein per day, the high-protein group used whey protein on top of their regular food. The normal-protein group got a non-caloric placebo drink.
Focusing on the latissimus dorsi (the “wings”), the researchers found that both groups experienced similar gains in size and strength. Extra protein had no effect on either.
Why the latissimus dorsi? For one, it hadn’t been studied much in this context, despite being the largest muscle in the human body. The second reason they chose it was “its relevance in many athletic gestures.” I can only assume they’re referring to the fist pump.
They also took a biopsy of the lats to analyze the effect the different protocols had on muscle fiber distribution. Normally, sticking with a resistance training program increases conversion of type 2x (super fast twitch, maximal force production, burns through energy) fibers into type 2A (fast twitch, less force production than 2x but more endurance). This indicates that your muscles are gaining metabolic efficiency. What once required super fast twitch fibers and maximal effort no longer does.
The high protein diet blunted the conversion, retaining more type 2x fibers. Is this good or bad?
More 2x fibers mean greater capacity for truly explosive movements. These are useful for power sports, sprints, weight lifting, and other activities requiring all-out max efforts. If those are the types of activities you enjoy, eating a bit more protein may help retain them.
More 2A fibers mean a greater capacity for strength-endurance. You can still go hard and heavy, but you’ll last a bit longer. These are important for athletes who engage in strength-endurance activities like cycling.
Realize that these are probably very small differences. When you get down into the weeds like this, mucking around with fiber types, you’ll see marginal returns. It’s important to keep an eye on the big picture: Eating more than double the protein improved neither size nor strength.
Does this mean you should definitely eat 0.8g/kg protein per day? No. Like I said in last week’s post, experiment. Try going lower in protein, just to see if you can get away with it and save money (protein is expensive, especially the high-quality stuff) while preserving your performance and body composition. Maybe you can’t, and higher protein just works better. That’s fine too.
Just another thing to file away for later consideration.
Thanks for reading, everyone. Take care!