Back in 2013, before his recent retirement, before his second Super Bowl win, Peyton Manning wasn’t sure if he would ever play football again. After surgeons removed the bulging cervical intervertebral disc in his neck, the pain was gone but then the rehab learning process was just beginning.
Damage to the surrounding nerves along with new metal hardware now holding together the vertebrae above and below the injured area caused a communications disruption between Manning’s brain and that well-trained right arm. The result was a future Hall of Fame quarterback having to relearn how to throw a football.
During a Green Bay Packers win over the Atlanta Falcons earlier this season, Peter King, the NFL's dean of sportswriters, found a new level of respect for quarterback Aaron Rodgers. Here's how King described one particular third and two play late in the first quarter:
"At the snap, Rodgers’ first look, a long one, was to the left for Nelson. Well covered. Quickly Rodgers turned to the right, to where Cobb was planting his foot in the ground three or four yards upfield and preparing to run a simple in-cut; at the same time, his cover man, cornerback Desmond Trufant, was going to have get through traffic to get to the ball if Rodgers was going to make the throw to Cobb."
You’ll hear the same thing over and over on high school and college football fields this month. “We just have to get our reps in.” “Time to knock the rust off and find our rhythm.” “Its all about timing and getting everyone in sync.”
The common theme for players is trying to increase the efficiency of their thinking and their movements, better known as muscle memory. By repeating the same motions and plays, practice may not become perfect but it certainly will improve. Now, neuroscientists at the University of Pittsburgh School of Medicine have found that brains actually do become more energy efficient after numerous repetitions by decreasing the electrical activity between neurons.
Unlike its meaning in strength conditioning, muscle memory in skill development is also referred to as motor learning. By stringing together an entire series of micro movements, whether it be a QB throwing a back shoulder pass or a linebacker executing an open field tackle, the recipe for the whole process becomes a procedural memory stored, obviously, in the brain not the muscles. Located in the brain’s primary motor cortex, this neural network has been shown to decrease in activity as athletes go through the learning process as it finds the most economical connection pathways between neurons.
Neuroscientist Peter Strick, professor in the Department of Neurobiology at the Pitt School of Medicine, wondered if this decline in metabolic activity coincided with a decrease in the number of neurons firing. He and his research team trained monkeys to do two tasks, one where they had to learn to anticipate a point appearing on a screen and one where they had to learn a short sequence of movements without any visual cues. The second task simulated a motor learning experience where they had to string together a complete movement, like throwing a bullet into double coverage.
They found that the level of neuron firing was the same with both tasks but the metabolic or connection activity required was lower for the internally remembered task. The research was just published in Nature Neuroscience.
“This tells us that practicing a skilled movement and the development of expertise leads to more efficient generation of neuron activity in the primary motor cortex to produce the movement. The increase in efficiency could be created by a number of factors such as more effective synapses, greater synchrony in inputs and more finely tuned inputs,” Dr. Strick noted. “What is really important is that our results indicate that practice changes the primary motor cortex so that it can become an important substrate for the storage of motor skills. Thus, the motor cortex is adaptable, or plastic.”
So, those endless drills and repetition really do physically change the structure of the brain. Getting football movements installed as muscle memory lets the player perform them automatically without thinking about each movement component.
To continue with mental reps even after the two a day practices end, many young QBs are turning to cognitive training tools, like the Axon QB app for iPad. The sooner the better before the season starts.
When describing his former teammate Joe Mauer’s hitting discipline, five-time MLB All-Star Jim Thome told ESPN, “Joe's the only teammate I've ever had who never gets fooled. And when I say 'never,' that's what I mean. Absolutely never." The fact that Mauer had more walks than strikeouts in 2012, while leading the league in on-base percentage, is not surprising to his Minnesota Twins’ manager Ron Gardenhire. "He takes (pitches) because he can," Gardenhire said. "Other guys aren't good enough."
Combine this knack of knowing when to swing with one of the sweetest strokes in baseball and the result is a three-time batting champion, a first for a catcher. Being able to unleash his trademark “quick swing” on just the right pitch has made Mauer into the model of brain-body coordination.
Now, Harvard bioengineer Maurice Smith has some new clues on how our brains are able to combine learned motor skills with all of the incoming cues from the external world. When we map out an action, like a baseball swing, in our brain, we use two different types of representations, intrinsic and extrinsic. “An intrinsic representation is one that’s body-based and procedural. It relates to the complex series of muscle and joint movements your body has to make to complete a task,” Smith said in a Harvard press release. For baseball players, they practice that swing and its collective parts over and over so that it becomes automatic.
The key, of course, is being able to not just swing a bat but use it to hit a ball travelling at 90 mph. This requires an ability to interpret the ball’s flight and intercept its path with contact. “Your brain must represent that action plan extrinsically, as it is an activity based in the world,” notes Smith.
Those two representations seem to be two different processes, first evaluate the situation and absorb the outside inputs (the approaching ball), then execute the well-rehearsed motor sequence to swing the bat. However, Smith’s Neuromotor Control Lab at Harvard learned last year that the two representations may actually be intertwined. “The predominant idea had been that in memory we maintain separate intrinsic and extrinsic representations of action and translate between the two when necessary,” said Smith. “But our work shows that memory representations are combinatorial rather than separate.”
Neurons store all of these different representations in a process known as gain-field encoding, which was thought to be just a common language interpreter between intrinsic and extrinsic. Not so fast, according to Smith.
In a unique experiment that tested volunteers ability to reach for a target with a cursor, the team was able to confirm that indeed the brain combines both types of representations internally. In baseball, that means the extrinsic model of the arriving pitch is stored alongside the intrinsic motor skill of swinging the bat.
“We found that this gain-field encoding, which leads to a combinatorial representation of space, is not simply an intermediary in the transformation between representations, but is in fact the encoding on which motor memories are based,” said Smith. “This suggests that the neurons which display gain-field encoding are the same ones that store the motor memories associated with the actions we learn.”
Obviously, at Joe Mauer’s level, those motor memories have evolved to a world class level. Perhaps his cross-training in other sports contributed to his advanced status. He was, after all, the only high school athlete to ever be named the USA Today National Player of the Year in both baseball and football, not to mention averaging 20 points a game for his basketball team.
