The Fitness Hormone

Let’s work smarter not harder by understanding how to optimize growth hormone. Growth hormone (GH) impacts how we build muscle & lose weight. ⁠

Let’s get sciency shall we. GH peaks in the first 30 minutes of moderate to high intensity exercise for women (it takes 60 minutes to peak in men fyi if you’re a man reading this). It has major benefits for focus & memory. It also increases the production of insulin-like growth factor which promotes tissue GROWTH and protein synthesis, aka the gains. ⁠

GH promotes lipolysis, the breakdown of stored fat (shoutout to human phys for that one). ⁠There are many other factors that can get in the way of lipoysis though. Including being too stressed, working out too much, poor sleep, and too much insulin (this is where nutrition comes in).

GH is also secreted during sleep (about 75% of total GH) whether we exercised that day or not, which is why sleep is so important to building muscle & losing weight. The most GH is secreted if we get into deep sleep AND if our insulin levels are pretty low…meaning we didn’t eat within about 2 hours of bed (or if we did it was pretty low in carbs). 7-9 hours of sleep has been shown to promote optimal GH secretion. However just to reiterate - eating or drinking that glass of wine before bed will impact sleep quality, insulin levels and growth hormone.

Remember insulin is the hormone secreted after we eat carbohydrates and protein (less is secreted but still some). This is where nutrition & physiology collide (my fave) to help you feel your best. Insulin can also impact growth hormone during a workout. SO…try to eat your preworkout snack 1-2 hours before if you can so insulin levels have come back down and you have enough energy to crush your workout. Sugary sports drinks during your workout will also inhibit GH secretion…but remember sleep is when 75% is secreted, so for my high school & college athlete girlies, don’t stress - having a snack may just give you the calories needed to you through that 2 hour practice.

One final note on optimizing GH and other hormones. A study found 20 minute suana, 30 minute cooling, the 20 more minutes sauna led to HUGE increases in growth hormone. Since I don’t have access to a sauna, I am starting to wear long sleeves & do more warm up exercises before my workouts so I sweat more. Then I follow workouts with 30 second blast of cold water…does it have the same effect? Not sure, but Andrew Hubermans makes a great point about benefits of hot/cold therapy for growth hormone,

“Growth hormone releasing neurons in the brain sit very closely & may even be intermixed with neurons that regulate heat and body temperature….Saunas also lead to decrease in cortisol but do not change testosterone & DHEA.” Hot & cold therapy have a multitude of benefits for brain & hormone health when used in small doses. The more we can push our bodies, the more resilient they become.

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PMID: 11086655⁠

doi.org/10.1016/j.tem.2020.04.005⁠

Check out Huberman Lab Episode 17 to learn more about Growth Hormone

Study on hot & cold therapy for GH: PMID: 33845653