WILL CYCLING MAKE ME CLEVERER?
Guillaume Martin is a two-time top-10 finisher at the Tour de France. The Frenchman also holds a master’s degree in philosophy and is the author of two books. Cycling has forged granite legs, bellow-like lungs and a heart that pumps out a reservoir’s worth of blood per beat. But has it moulded an intellectual superman? There’s an increasing body of research to suggest that exercise is as beneficial for your brain as your body…
Dr Larissa True is associate professor in the department of kinesiology at New Mexico University and is an expert in motor control (movement), the brain and exercise. “Brainderived neurotropic factor, or BDNF, impacts brain function,” True tells us. “This is secreted in the brain and influences neurofunction by regeneration of neurons [nerve cells that send messages] throughout the neural system. [BDNF gives] your brain greater plasticity and improves long-term repair. BDNF is also important in motor learning and long- and shortterm memory. That secretion is activity-dependent, meaning that more BDNF is secreted when
a person is active. The more active you are, the more BDNF is secreted, the more synapses are repaired.”
BDNF has been tagged ‘fertiliser for the brain’ and, according to a 2022 study in the Journal of Sport and Health Science, you can enjoy a greater cerebral spray of Miracle-Gro through highintensity exercise; in cycling terms, you’ll gain more by climbing Alpe d’Huez than cruising along the Fens.
One of the mechanisms for the ramping up of BDNF is, says an earlier 2016 study, elevated levels of the ketone body betahydroxybutyrate, stimulated through long, fatiguing exercise. This is the endogenous version – i.e. created internally – but it lends weight to the extraneous version that’s caused such a stir in professional cycling. Since Kieran Clarke, an Oxford University
professor, created endogenous ketone esters years ago (now marketed as deltaG), which were reportedly used by British Cycling at the 2012 Olympics, they’ve been shown to boost recovery, improve endurance and increase levels of EPO (erythropoietin, of which the injected blood-boosting version results in a doping ban. Cue Lance Armstrong, Jan Ullrich, etc). Mentally, they’ve been shown to maintain focus, as per
“Aerobic exercise delivers a greater boost for cognitive ability, while strength training is more effective at enhancing executive function”
the above. They’re controversial and have been banned by the Movement for Credible Cycling because little is known about the side-effects.
You can buy pure BDNF in tablet form, though the tablets’ effectiveness is contentious as BDNF is a clunky molecule that doesn’t pass easily from blood to the brain. Best stick to hard riding for a BDNF boost.
American Martin Paulus is president of the Laureate Institute for Brain Research and has undertaken numerous studies into the machinations of the brain. One used fMRI (functional magnetic resonance imaging) to measure the brain activity of Navy Seals during a breathing exercise. What did Paulus find?
That high performers prepare their mind before a challenge but don’t respond as emotionally to the challenge itself. “In cognitive terms this is often referred to as ‘proactive control’. The brain readies itself, so isn’t overwhelmed by the challenge.” In essence, the Navy Seals devoted greater processing power to the emotional situation at hand for a more controlled outcome.
Paulus and his team identified two areas of the brain that were particularly sensitive to this challenge: the anterior cingulate cortex (ACC) and insular cortex. “They naturally link together, taking information from the peripheries and equilibrating that with information from the rest of your brain.
“Say you’re hungry. That’s a peripheral feeling. Your blood sugar is low, sending signals. But the brain might also be thinking ‘I’m going for a nice dinner tonight’. So, what’s happening is that you might feel hungry, but you know you’re going for dinner later. So, you must integrate these two signals to guide your action.”
Building resilience
High performers such as the Navy Seals had repeatedly been put through physically and mentally stressful situations. This had nurtured a non-judgmental attentional focus on the body; a greater awareness of bodily signals thanks to acute subjectivity. This compares to non-resilient folk who overload ‘judgment’ on the attentional process and catastrophise the experience. This can also be seen in these brain areas, says Paulus.
As keen cyclists, your ACC and insular cortex is honed for well-rounded decision making, whether that’s pacing or taking a sharp corner. But you can take it to Navy Seal levels thanks to mindfulness. “The same areas light up during mindfulness,” says Paulus. “It’s all about tuning into your bodily signals.”
Paulus adds, “One tip for a cyclist is to pay attention to your body and minimise judgment, whether it’s positive or negative. If you’re in a sportive, you’re in an energy balance. When you’re paying attention to your body in a non-judgmental way you can integrate that information. Do I need to slow down? Do I need to drink? By learning to pay attention to body signals, you will cycle better.”
Advantages all round
This is all heartening stuff but what about the degree of exertion? Physiologically, ride through the intensity spectrum and you’ll go from fat-burning to anaerobic efforts that are vital for steep, speedy efforts. We’ve already learned that highintensity pedalling is a BDNF bonanza, but what else does the neuroscience say?
A 2017 review into exercise and cognition found that aerobic exercise delivers a greater boost for cognitive ability (problem solving), while strength training is more effective at enhancing executive function (attention, planning), memory and working memory. In short, keep on pedalling to boost your body and brain.
Crank length is measured from the centre of the bottom bracket axle to the centre of the pedal axle. The three most common crank lengths are 170mm, 172.5mm and 175mm. Small bikes tend to come with 170mm cranks, medium with 172.5mm and large with 175mm. Shimano, SRAM and Campagnolo offer cranks as short as 165mm at most groupset levels, and up to 180mm in some cases.
Extra small frames (typically those with a top-tube of 50cm or shorter) are increasingly coming fitted with 165mm cranks, but it’s rare to see 167.5mm cranks, or anything g longer than 175mm, specced d on frames of any size.
Given that cranks are levers, and we know that longer levers amplify the effect of a given input force, it’s tempting to conclude that longer cranks might increase your power output. But is that the case? Over to Shimano: “170-175mm cranks provide an optimal balance between rotational inertia [the torque required to turn the crank], rotational speed [i.e. cadence – shorter cranks have to be spun faster to achieve the same power output], frame design [longer cranks require a higher BB to achieve the same pedalling clearance] and biometric issues [longer cranks place greater demands on joints and muscles as the turning circle is larger]”. Basically, Shimano thinks 170 to 175mm is the Goldilocks zone for most people and most bikes.
For Phil Burt, a leading physiotherapist and bike fitter, crank length issues – such as an inability to spin high cadences, difficulty breathing, joint or muscular pain, or the rider’s knees hitting the chest or handlebars when riding in an aerodynamic position – almost always stem from riders using cranks that are too long for their bike position or physiology.
In contrast, Burt doesn’t see many problems arising from riders using cranks that are shorter. The likelihood that your cranks are too long largely depends on your leg length. This is because cranks make up a larger percentage of a shorter rider’s leg length. A 175mm crank is likely to be a smaller percentage of a very tall person’s leg length than a 170mm crank is for a shorter person.
“For leading physio Phil Burt, crank length issues often stem from riders using cranks that are too long for their physiology”