As a business dedicated to selling the best range of sports nutrition supplements, it’s only natural to gravitate towards ‘nutritional’ solutions when seeking to maximise or promote natural growth hormone (GH) release. But when talking about strategies to increase growth hormone levels, one must remember to keep it all in perspective and try stray from a minimalistic approach. Nutritional manipulation of growth hormone is nonetheless a very important and popular part of an athlete’s supplement arsenal and we encourage you to read our Natural GH Supplements Guide on this topic.
Rather than cover the latest developments in nutritional supplements designed to promote growth hormone release, this article will focus on the most basic and fundamental mechanisms governing GH release as well as some lesser-known but nonetheless important contributors.
Far and away, the most powerful stimulator of natural GH release is sleep. More specifically, research has uncovered that the amount of slow wave sleep is positively correlated with GH release1, 2. So you can be training the house down and taking a bunch of supplements but if you’re not getting enough good quality sleep – you’re potentially wasting much of your time and money.
The average gym-junkie probably knows that exercise itself causes a release in GH. But looking more closely at the research in this area, a number of studies suggest that while exercise does cause a rise in GH, the net GH levels throughout the day from an acute single one-off weight session tend to be the same as if no exercise was performed6.
While scientists are still piecing together the exact mechanisms by which different types of exercise modulates GH levels, some of the factors they are sure of is that the work-rest interval coupled with load and frequency are correlated with GH release, such that greater workloads produce greater release5. In fact there is also evidence to suggest that if either aerobic7 or resistance8 exercise is carried out with the same workload over a period of weeks, GH release actually decreases after a number of weeks.
So in many respects it would appear that some of the proven principles for increased strength and muscle gains are also true for continued healthy GH release. These include the notions of variation in training stimulus and progressive overload/periodisation. In support of this, there are studies both in aerobic4 and strength training9 that support the notion of raised growth hormone levels following a period of intense progressive training. The overriding principle is that a critical threshold of exercise intensity must be reached on a daily basis to stimulate GH release. So if you’re not prepared to train hard, you must be prepared to compromise on GH release.
Closely connected to the above principle of training intensity is the relationship between training status and GH release. In a nutshell, athletes who have been training consistently for several years tend to show greater GH release than the coach potato who’s just decided to take up an exercise program. As an example, a study compared middle-aged endurance-trained cyclists riding approximately 10 hours per week for an average of 300km for the past 10 years, with a group of middle-aged sedentary men. When subjected to two bouts of 60 min cycling; one performed below and the other above ventilatory threshold, subjects from the endurance-trained group showed both higher basal GH levels and a threefold higher GH response to the cycling exercise10. So when it comes to maximising GH release, you have to be prepared for the long haul and put in the hours day-in day-out, while waiting on Nature to do its work.
Severe calorie restriction is commonplace for bodybuilders in pre-competition phase, but one of the major drawbacks with calorie restriction is that it has the potential to reduce GH release. For example, a study by researchers from California took a group of young healthy men and subjected them to a 7-day strenuous exercise program in which they were randomly assigned to either a positive energy balance (calorie expenditure less than calorie intake) or negative energy balance (calorie expenditure greater than calorie intake) group11. During the strenuous exercise program, free and total IGF-1 levels decreased substantially in the underfed subjects but remained stable in the overfed group. GH levels are closely tied to IGF-1 levels so the results of the study can also be interpreted such that a negative energy balance in conjunction with strenuous training leads to a decrease in GH levels/release. Therefore, it’s important that athletes carefully manage their training intensity during periods of severe calorie restriction so as to minimise major decreases in GH release.
Many may not be aware of the important complimentary role that serotonin plays in GH release. Serotonin is one of the body’s main neurotransmitters that is synthesised from tryptophan and involved in the regulation of mood, appetite, and sleep12. The branched chain amino acids (BCAA's), leucine, isoleucine and valine all compete for the same carrier as tryptophan in the blood brain barrier; meaning that tryptophan transport into the brain is diminished when given along with BCAA's. BCAA's are commonly promoted for recovery and are often recommended to be taken after training and before bed to minimize muscle tissue breakdown and muscle soreness. However, studies have shown growth hormone release to be reduced when serotonin blocking agents or drugs are administered3. So it may be prudent to avoid taking excessive amounts of BCAA's or protein at night if trying to maximise growth hormone release5. It’s especially important to avoid taking BCAA's in close proximity to GH supplements.
In summing up, its important to remember the factors governing growth hormone release are many and varied. In keeping with this, one has to resist taking an overly simplistic approach when trying to maximise their anabolic drive and associated growth hormone release. By all means, go for broke with your favourite GH supplement, but if you want the full benefits, you had better be getting the basics right such as proper sleep, training and diet. Once you're on top of these, the GH supplement is really just the icing on the cake.
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