by Dan Trink T-Nation
How does training with weights change your body?
Your high school PE teacher – back when schools still made physical education part of the curriculum – likely offered the classic “house in the hurricane analogy.”
“Training affects your muscles like a minor hurricane does a house. It cracks windows, rips off shingles, and busts up the fence. But if you don’t overdo it, and give your body the materials (food) and the time to rest and make repairs, it will come back bigger and stronger than before.”
Sadly, even your eighth-grade self knew this was way too simplistic, but you didn’t press the matter. You knew better than to lock horns with an overly caffeinated gym teacher armed with a whistle.
Fact is, strength training does more than just create muscle damage. It releases a variety of hormones that also influence how you’ll adapt and grow from your training session.
What many trainees don’t know is how to manipulate this hormonal cascade to get bigger, stronger, and leaner. Is there an ideal way to structure your training to get the most out of your hormonal environment?
Let’s Take A Look At The Numbers
Research findings, in combination with anecdotal evidence from the training floor, suggest that it is possible. While many hormones come into play during resistance training, the four major ones are Testosterone, growth hormone (GH), insulin-like growth factor (IGF), and cortisol. These are the most researched hormones in relation to strength training, and the science supporting their role in the process appears solid.
No hormone gets as much press in strength training as the capital T and for good reason. Testosterone has an important role in the signaling of protein synthesis and reduces the impact of catabolic hormones.
It’s lesser known, but no less important role is as a facilitator for other hormonal mechanisms such as growth hormone and IGF-1 in the anabolic process (1).
Simply stated, Testosterone is anabolic on its own and makes other hormones more anabolic just by showing up.
Although there are several factors that stimulate elevations in Testosterone, it appears that exercise selection may be the key variable. Large, compound exercises such as the Olympic lifts (2), deadlifts (3), and jump squats have been shown to produce large elevations in Testosterone as compared to small-mass exercises (4, 5).
Research also supports that sequencing these movements properly is critical. Large muscle-mass, multi-joint movements placed early in the program tend to increase strength and lead to elevated Testosterone levels throughout the workout.
The main function of growth hormone is in promoting tissue anabolism. So if you want muscle cells to increase in size, GH is a key factor.
Research shows that strength protocols that elicit high levels of blood lactate tend to produce the most substantial GH responses (6, 7, 8, 9, 10). Lactate training is often affiliated with the common parameters of hypertrophy training.
So protocols that are relatively high in intensity (75% of 1RM), high volume, use large amounts of muscle mass, and have relatively short rest periods tend to get GH flowing.
It’s also worth noting that much of GH is released at night during sleep. So getting an appropriate amount of sleep and recovery is critical to maximize its effects.
IGF (Insulin-Like Growth Factor)
The job of IGF is to mediate the many actions of growth hormone. An analogy may help: if GH is you in a Las Vegas strip club, IGF is like a huge stack of dollar bills.
Another way to look at it is, if insulin is the key hormone used to signal glucose to enter a cell, IGF works in a similar way for GH. IGF also aids in protein synthesis during strength training and therefore enhance hypertrophy (11).
Since IGF’s main job is to work concurrently with GH, similar resistance training protocols as above should be followed to maximize this hormone’s effects.
As opposed to the hormones discussed earlier, cortisol is actually catabolic in nature. What that means is that this stress-response hormone breaks down tissue. So rather than trying to maximize its response, we’re going to try to minimize it.
The best way to shunt the cortisol response from training is likely through nutritional interventions, specifically an insulin-spiking post-workout shake (such as Surge® Recovery, though training factors can also come into play.
Cortisol spikes during very metabolically demanding training protocols that are high in total volume with very short rest periods. However, typical strength and power training parameters tend to have little to no effect on cortisol. This is certainly something to account for when designing your program.
Interestingly, as cortisol is catabolic, it does stimulate lypolysis of adipose tissue (breakdown of fats), so if you’re training exclusively for fat loss, spiking cortisol may be a good thing.
Just remember, it’s a fine line between fat breakdown and muscle breakdown, so if you over do the metabolic training, you may end up with some muscle loss to accompany your lower body fat.
Here’s a quick review:
Testosterone, growth hormone, and IGF are major anabolic hormones that can be manipulated to a degree through specific training variables.
Optimal strength and hypertrophy training parameters tend to maximize the benefits of the anabolic hormones.
Cortisol is a catabolic hormone that’s released mainly during very metabolically demanding training with short rest periods. Therefore, its effect should be managed.
This program has yielded excellent results with many clients and colleagues who’ve tried it – to what degree is due to modulating hormones or simply from a general training effect is open to debate.
I just know that it works, reliably and consistently.
Granted, any training program that uses challenging loads will have some effect on the hormonal system, but “some” effect and “optimal” effect are two different things. If you maximize the effect of these major hormonal players you’re sure to be one step closer to a body composition that stands out.
1. Giustina A, Veldhuis JD. Pathophysiology of the neuroregulation of growth hormone secretion in experimental animals and the human. Endocr Rev 1998;19:717-797.
2. Kraemer, WJ, Fry AC, Warren BJ, et. al. Acute hormonal responses in elite junior weightlifters. Int J Sports Med 1992;13:103-109.
3. Fahey TD, Rolph R, Moungmee P, et al. Serum testosterone, body composition and strength of young adults. Med Sci Sports Exerc 1976;8:31-34.
4. Ratamess NA, Kraemer WJ, Volek JS, et al. Androgen receptor content following heavy resistance exercise in men. J Steroid Biochem Mol Bio 2005;93(1):35-42.
5. Ballor DL, Becque MD, Katch VL. Metabolic responses during hydraulic resistance exercise. Med Sci Sports Exerc 1987;19:363-367.
6. Kraemer WJ, Marchitelli L, Gordon SE, et. al. Hormonal and growth factor responses to heavy resistance exercise protocols. J Appl Physiol 1990;69:1442-1450.
7. Kraemer WJ, Gordon SE, Fleck SJ, et. al. Endogenous anabolic hormonal and growth factor responses to heavy resistance exercise in males and females. Int J Sports Med 1991;12:228-235
8. Gotshalk LA, Loebel, CC, Nindl BC, et. al. Hormonal responses to multiset versus single-set heavy resistance exercise protocols. Can J Appl Physiol 1997;22:244-255
9. Kraemer WJ, Volek JS, French DN, et.al. The effects of L-carnitine L-tartrate supplementation on hormonal responses to resistance exercise and recovery. J Strength Cond Res 2003;17:455-462
10. Hoffman, JR, Im J, Rundell KW, et.al. Effect of muscle oxygenation during resistance exercise on anabolic hormone response. Med Sci Sports Exerc 2003;35:1929-1934
11. Kahn, SM, Hyrb DJ, Nakhla AM, et. al. Sex hormone-binding globulin is synthesized in target cells. J Endocrinol 2002;175:113-120