Even though I don’t ride bikes, I’ve always been a dedicated exercise enthusiast. In my early to mid 30s, running a half marathon every weekend was a regular part of my life. Then, in my mid 30’s I picked up kettlebell training and started competing in competitions. Now in my 40s, I continue to push myself, not necessarily to achieve a specific time in a 21K race, but to reap the benefits of exerkines, a relatively new concept in exercise science. The concept of exerkines truly came to surface around 2016 when researchers started to realize that chemical messengers released from exercise could have cardioprotective, hepatoprotective and neuroprotective benefits. We know that exercise creates a short-term inflammatory state, but then the body up-regulates anti-inflammatory mechanisms shortly after to repair the damage. That is an example of how these exerkines can create effects within the body that are protective to all organs.
Exerkines are chemical messengers released during both acute and chronic exercise, capable of modulating anti-inflammatory and immune-supporting benefits across various organs. Among the well-researched organs that release these exerkines are skeletal muscles, the heart, the brain, the liver, and both white and brown adipose tissue. Research suggests significant cross-talk between these organs through the modulation of these chemical messengers. Since skeletal muscle makes up so much of our body’s internal structure, it is an important aspect of health to be able to utilize their exerkines to our advantage in healthy aging.
While there are numerous exerkines in the body, some of the most talked about include Brain-Derived Neurotrophic Factor (BDNF), lactate, nitric oxide, and myostatin. These are just a few among many. Today’s blog will focus on two of my favourites: BDNF and lactate. I will also focus a little on how exercise shapes the gut microbiome.
Exercise whether in the form of aerobic training, resistance training, or High-Intensity Interval Training (HIIT) has gained popularity for its efficiency and effectiveness in improving cardiovascular fitness and metabolic health but it’s effects on the brain are its most valued aspect we are all looking for. It’s exercise’s effects on the body that has the ability to modulate hormones, neurotransmitters, lipids, and protein which then have a knock on effect on caloric intake, ketogenesis, and insulin sensitivity.
1. Enhanced Cognitive Function: HIIT has been shown to improve cognitive functions such as memory, attention, and executive function. The intense bursts of activity increase blood flow to the brain, promoting the delivery of oxygen and nutrients essential for brain health.
2. Neurogenesis: Exercise stimulates the production of brain-derived neurotrophic factor (BDNF), a key protein that supports the growth, survival, and differentiation of neurons. Increased levels of BDNF are associated with enhanced learning and memory.
3. Mood Regulation: A bout of High Intensity Exercise can lead to the release of endorphins and other mood-enhancing exerkines, reducing symptoms of anxiety and depression. This mood-boosting effect is often referred to “runner’s high”
The Role of Lactate Threshold in Brain Health
The lactate threshold is the exercise intensity at which lactate begins to accumulate in the blood. Training at or near this threshold improves the body’s ability to clear lactate, enhancing endurance and performance. Interestingly, lactate also plays a crucial role in brain function. This is why elite athletes, will always have a lactate meter to check their levels of lactate when they are training.
1. Energy Supply: Lactate serves as an important energy substrate for the brain, especially during intense exercise when glucose availability may be limited. It helps maintain brain energy homeostasis, supporting cognitive function during and after workouts.
2. Neuroprotective Effects: Research suggests that lactate can protect neurons from oxidative stress and excitotoxicity, potentially reducing the risk of neurodegenerative diseases.
3. Synaptic Plasticity: Lactate has been shown to enhance synaptic plasticity, the ability of synapses to strengthen or weaken over time, which is critical for learning and memory.
Exercise and the Gut Microbiome
The gut microbiome, a complex community of microorganisms residing in the digestive tract, plays a crucial role in overall health. Exercise has been shown to positively influence the gut microbiome, leading to a host of benefits.
1. Diversity of Gut Microbes: Regular physical activity, including HIIT, has been associated with increased microbial diversity in the gut. A diverse microbiome is linked to better immune function, reduced inflammation, and improved metabolic health.
2. Short-Chain Fatty Acids (SCFAs): Exercise promotes the growth of beneficial gut bacteria that produce short-chain fatty acids like butyrate. SCFAs are essential for maintaining gut health, reducing inflammation, and supporting the gut-brain axis.
3. Gut-Brain Axis: The gut and brain communicate through the gut-brain axis, a bidirectional signalling pathway. By positively influencing the gut microbiome, exercise can enhance mood, reduce anxiety, and improve cognitive function.
Happy Sunday Everyone!