Like many people, I used to struggle to keep a consistent exercise routine. Armed with nothing but a vague sense that it was good for me and usually extra motivation to lose weight, I’d start something only to discard it in a couple of days or weeks. This cycle changed when my vague sense developed into a concrete understanding of how exercise improves almost every aspect of my life. Now, I’ve been exercising consistently for 2.5 years, and it started when I found out how exercise benefits the brain.
The benefits of exercise on the brain include improving learning, stress management, anxiety, mood, and focus. These effects are so robust that people commonly stop taking medications for anxiety, depression, and ADHD when they start exercising consistently. The mechanisms for this are detailed in Spark: The Revolutionary New Science of Exercise and the Brain by John Ratey, MD, but the central mechanism is brain-derived neurotrophic factor (BDNF). BDNF causes neuron growth and is triggered by exercise. It promotes positive effects, such as improving learning and mood, while protecting against negative effects, such as cell death. Studies have shown that more physically fit kids do better in school. In addition, starting the school day with exercise improves students’ performance more than studying for an extra hour.
Once the brain effects had me hooked, I kept learning more benefits of exercise.
- Stress tolerance – Because exercise stresses you in a way that you control, you learn to be more comfortable at higher levels of stress, increasing your stress tolerance.
- Stress management – Further, it allows cortisol to be broken down quickly. Evolutionarily, stressors increased our cortisol, so we could physically escape danger. Physical movement broke down this excess cortisol. Now we experience mental stressors that require no movement, so our cortisol rises but doesn’t clear out of the system quickly, causing long-term negative effects.
- Discipline – Exercise involves 1) starting to exercise when you don’t feel like it and 2) pushing yourself during exercise when you’d rather quit. Both of which require discipline. I didn’t expect, however, that this discipline would transfer to other aspects of my life. I used to procrastinate 5-minute administrative tasks for weeks. After exercising consistently, I notice that I just …do them.
- Dopamine – Exercise improves the dopamine system in a few ways. One of the long-term benefits is that if you stick with a routine that you find challenging, you’ll likely start to enjoy it.
- Serotonin – Exercise also improves the serotonin system, which is why it can improve mood and alleviate depression and anxiety. Serotonin is also the precursor to melatonin, which helps people sleep better.
Rule 1: I start every day with a walk (and now mobility exercises).
Every morning, within 30 minutes of walking up, I head outside for a walk. I’ll walk for 20 minutes aiming for “zone 2” cardio, which means that I breathe through my nose but almost have to breathe through my mouth. On days when I’m also doing strength training, I’ll walk for only 10 minutes as a warm-up activity. This morning walk has other benefits described in the sleep routines post. It helps to clear the natural surge of cortisol that wakes you up, and early outdoor sunlight helps set healthy circadian rhythms.
Sometime after my walk, I’ll do a 5- to 10-minute mobility session. This session staves off declines in flexibility and joint health. I started doing this mobility session after strength training for 2 years because I noticed that some of my joints would occasionally hurt (probably because I, shamefully, wasn’t doing any sort of warm-up other than walking). My session includes stretches for wrists, neck, spine, shoulders, hips, and ankles – the major joints that move in more than one direction.
Rule 2: I do strength training 2-3x per week.
For the first year, I would do two, 45-minute, full-body strength training sessions per week. I was in an apartment at that point with a small gym, so I mostly used dumbbells. This ended up being a really good place to start because it helps symmetrical development. For example, if I was bench pressing a 50lb barbell, I could develop an imbalance where my right side is doing more work than the left. An imbalance is much harder when pressing a 25lb dumbbell on each side. Now that I’m conditioned and trained, I do three, up-to-60-minute, full-body sessions per week. I use an even split of barbell movements, which helps full-body coordination, and dumbbell or band movements, which maintains symmetry.
For me, I enjoy strength training more than other types of exercise I’ve tried, especially for getting the most out of my exercise time. For anyone else, the best exercise is the one that they’ll do consistently. I loathe most kinds of cardio exercise, but ideally, exercise routines include both cardio and strength. Ideally means don’t let perfect become the enemy of good. It took me 2 years of consistent exercise before I had the discipline to do the cardio I know I should’ve been doing all along. In addition, don’t overdo it. Soreness is not the goal. If you’re regularly sore or sore for more than one day, you did too much.
We often hear that cardio is important for health, but strength is equally important. Strength and muscle mass are especially important as you age, and they decline every decade by 8-10% after age 50. Strength is important for not injuring yourself and maintaining independence. Muscle mass is important for balancing hormones, especially those that contribute to diabetes, cardiovascular disease, and other chronic diseases. Strength and muscle mass are so important that there is a 350% and 200% increase in all-cause mortality between high and low strength and muscle mass groups after age 50.
Rule 3: I do 1 session per week at 80%+ of my maximum heart rate.
Close to maximum heart rate – the dreaded “zone 5” cardio and the worst 4 minutes of my entire week. This is the session that I couldn’t commit to until I’d been exercising like clockwork for 2 full years. I’ve never heard people talk about zone 5 without a drawn-out “uuuuuggggghhhhh.” Or maybe it’s just confirmation bias. Regardless, pushing your cardiovascular system is really good for you. It creates new capillaries, making sure that your muscles and brain get enough oxygen. High cardiovascular health decreases all-cause mortality, just like strength and muscle mass. It’s also one of those things that if you do it once a week, you get about 90% of the benefit of doing it more regularly.
For me, the most painless way of doing this is to hop on the stationary bike, warm up, and go all out for 4 minutes. I know many other people prefer high-intensity interval training or HIIT, but that takes longer for me to reach 80%+ max heart rate. If you opt for an interval approach, popular options are Tabata or the 7-minute workout. Once you’re conditioned, though, you might need to repeat these multiple times. You should feel like you’re giving everything you have, but make sure that you work up to it if you’re not already used to cardio.
There’s a lot of good information about exercise on The Huberman Lab Podcast with Andrew Huberman and The Drive with Peter Attia. I won’t recommend any one video in particular because it depends on what type of exercise you’re interested in. I also highly recommend Mind Pump for people of all experience levels. Mind Pump is a podcast by three personal trainers with different specialties. From decades of working with clients, they have a lot of experience explaining things to be accessible, and they temper the scientific literature with abundant knowledge of human psychology and what works for real people. They also have great form videos for learning movements.
For more blog posts about wellness, return to the wellness series page.
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