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The High Performance Journal - July 1st, 2025

Something I hate to admit is that I used to be one of those "I'll sleep when I'm dead" type of guys.

4 hours of sleep? No problem. Eating dinner at 10:00 PM? Totally normal. Staying up until the wee hours past midnight? Just part of the hustle.

What I didn't realize was that I was disrupting my 24-hour internal clock, known as a circadian rhythm.

This clock adjusts your hormones, body temperature, and energy levels based on what time it thinks it is.

Follow your rhythms and you get more energy, better health, and a leaner body.

Following a disrupted circadian rhythm can lead to obesity, diabetes, heart disease, and even depression.

In today's newsletter, I want to show you how to align yourself with your circadian rhythms, allowing you to optimize your body and perform at your highest levels.

The Complete Guide On Optimizing Your Body With Your Circadian Rhythms

A Circadian Rhythm (aka CR) is a biological cycle that runs for 24 hours every day.

Circadian rhythms can influence sleep-wake cycles, hormone release, eating habits and digestion, body temperature, and other important bodily functions.

They respond primarily to light, darkness, eating habits, and physical activity.

I wake up at 6am, eat my final meal by 5pm & go to sleep by 9:30pm and I feel incredible.

Life is way more enjoyable when you're attuned to your natural rhythms.

— Dan Go (@FitFounder) April 2, 2023

This 24-hour process is driven by your internal clock, and it’s been widely researched in plants, animals, fungi, and, yes, humans.

Simply put, you, I, your dog, your cat, your mom, and every other living thing on this planet have an inner clock that coordinates our daily rhythms.

Evidence-Based Benefits of Following Your Circadian Rhythms

• Optimized sleep
• Strong immune function
• Enhanced cognitive function
• Improved cardiovascular health
• Improved metabolism and weight control
• Improved mood and mental health stability

Evidence-Based Dangers of Disrupting Your Circadian Rhythms

• Low energy
• Sleep disturbances
• Increased risk of diseases
• Hormonal and immune dysfunction
• Increased risk of accidents and errors
• Mental health and cognitive impairment

The Key to Activating Your Circadian Rhythms

Your circadian rhythms are trained through the master clock in your brain called the Suprachiasmatic Nucleus (aka SCN).

The SCN uses light signals and your skin, which responds to light, temperature, and food.

Other important cues include the timing of meals, work, physical activity, and social routines. All these signals help set and maintain our body’s daily rhythms for better health and performance.

Ideally, we want to use these to our advantage and train our bodies to align with our circadian rhythms instead of having them work against us.

Here's how:

Step 1: Consistent Sleep Times

No matter how hard it is, one of the most critical ways to start training your circadian rhythms is to start going to bed and waking up at the same time every single day, even on the weekend.

If this is hard for you, then commit to an optimized schedule for about two weeks. This is around the same time frame that your body needs to start expecting to sleep and wake at the same times.

One of the best ways to align yourself with your circadian rhythms is to align your sleep and wake times to the rising and setting of the sun.

If this is not realistic for you at this very moment, you can progressively overload yourself when it comes to sleep by sleeping a little bit earlier and waking up a little bit earlier and using the 2-week adaptation cycle mentioned previously.

Step 2: Light Exposure

Think of light as the remote control for your internal clock.

The most important times to get light are in the morning and at sunset.

Getting outside within 30 minutes to an hour upon waking, even if it's just for 10 to 15 minutes, tells your brain it's daytime. Let's wake up properly.

This stops the production of melatonin (the sleepy hormone) and ramps up cortisol (the wake-up hormone).

When the evening comes, you want to be able to attune your environment as if night time is coming.

This means dimming your lights around sunset, putting your devices away at least an hour before bed, or wearing blue light blockers.

When the eyes take in blue light, especially in the evenings when you're trying to rest, this can keep you wired and prevent you from going to sleep, which will lead to a downstream consequence of dysregulating your hormones and appetite the next day.

Step 3: You Are What You Eat

Your digestive system has its own circadian rhythm, and it works best during the day.

I eat roughly around the same times every day, and this trains my body to start preparing for food when it expects it, which makes digestion more efficient.

The best eating schedule starts at the end of the day:

• 3 to 5 hours before going to sleep: Eat your final meal
• 1 to 2 hours upon waking: Eat a high-protein (30+ grams of protein) breakfast
• In between breakfast and dinner: Eat your second meal

You want to have an eating window of about 10-12 hours and eat at roughly the same times each day to train your body to expect food and when it shouldn't.

We've used this eating style in our ​Lean Body 90​ and ​private coaching​ programs. The vast majority of customers and clients report back that weight loss becomes more effortless by following the right timing.

Step 4: Timing Your Exercise

One of the worst times to work out for your circadian rhythms is late at night.

Evening workouts can mess up your sleep because exercise raises your body temperature while releasing energizing hormones and endorphins.

The best time to work out, according to your circadian rhythms, is around 2 to 3 o'clock. That's when you have your fastest reaction times and best coordination.

If you can't do an afternoon workout, then you can train your body to expect exercise early morning.

Step 5: Your Evening Wind Down Routine

Your evening routine is as important, if not more important, than your morning routine. Having an actual routine to prepare you for sleep is a massive net benefit to your circadian rhythms.

About 2 hours before bed, I start winding down:

• Dim the lights throughout the house
• Put my phone in another room (this was the hardest part)
• Do something relaxing, like reading or light stretching
• Keep the bedroom cool (around 65-68°F)

I'm not perfect with this every night, but when I stick to it, I fall asleep so much faster.

How To Sabotage Your Circadian Rhythms

1. Caffeine After Lunch: Caffeine stays in your system for 6-8 hours, meaning that 3 PM coffee can still affect sleep at 10 PM. Set a hard cutoff for caffeine after noon.
2. Weekend Sleep-Ins: Sleeping until noon on Saturday felt great in the moment, but it was basically giving myself jet lag every week. Now I might sleep in an extra hour on weekends, but I try to stay within an hour of my normal wake time.
3. Late-Night Eating: Those midnight snacks were telling my body it was still daytime. You need to give your digestive system a break.

How To Make It Stick

The key to change is to do things gradually. Don't try to overhaul your entire schedule overnight. Trust me, I tried this. It didn't work.

I started by moving my bedtime and wake time by 15 minutes, 15 to 20 minutes earlier every few weeks until I hit my target. For meal timing, I slowly shifted dinner earlier by 30 minutes a week every 6-8 weeks.

Pay attention to how you feel. After a few weeks of consistent sleep and meal times, you'll notice some patterns.

We Are "When" We Do It

Once I got my circadian rhythms aligned, everything else got easier.

I had more energy, and it was stabilized throughout the day. I stopped having 3pm crashes.

My workouts felt better because I wasn't constantly tired. My mood improved because my hormones were more stable. And it was easier to keep my body lean as a result of having my hunger regulated for me.

The key is not to try to fix everything at once. Your body needs time to adjust, and building one habit at a time is way more sustainable.

The circadian rhythm wants to help you feel good. You just have to stop fighting it and start working with it instead.

Onward and upward. 🚀

- Dan

When you're ready, here are 3 ways I can help:

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References

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Disclaimer: This email is provided for educational and informational purposes only and does not constitute providing medical advice or professional services. The information provided should not be used for diagnosing or treating a health problem or disease, and those seeking personal medical advice should consult with a licensed physician.