This morning one of my most dear friends posted to Facebook that she was so happy after an interview she just conducted with Mark Sisson. (This woman may or may not be one of the hosts of the ever famous The Paleo View podcast.) The reason she was so happy, at least in part, was that Mark helped her understand better how to re-fuel after a work out. Most fitness gurus know that muscle building is the most efficient when you refuel after a workout with carbohydrate and protein. What we forget to often talk about are the hormonal effects that occur at this time, too.
This is especially important for women.
When I was diagnosed with PCOS, I searched high and low for a link between muscles and testosterone. I thought maybe my high muscle mass was causing my PCOS. Exercise junkies on internet forums often hypothesized that this was the case…. that increased muscle mass causes women’s testosterone levels to go up. That made intuitive sense to these people. Men have muscles, and lots of testosterone.
But I couldn’t find any good science to back it up.
Today, still, women with high testosterone levels ask me all the time if their exercise habits have anything to do with it. Just last week I had to shrug my shoulders as a fellow blogger and say ‘hm sorry I don’t have a good answer for you?’
Then Stacy and Mark gave me the idea to look into the science of post-workout meals.
(THIS is my favorite post-workout snack.)
Because what’s important for the relationship between exercise and testosterone levels is not muscle mass, nor even the intensity of the workout.
It is, instead, whether or not you eat afterwards.
What happens when you workout and afterward
During the course of any kind of strenuous activity — whether more in the vein of endurance / cardio or in high intensity weight lifting — the body burns through its glycogen stores. Glycogen, in essence, is a form of sugar. It’s stored in the muscles. It’s one of the body’s favorite fuel sources for exercise. Athletes almost always start a demanding workout with full glycogen stores. Otherwise, they will have less fuel for their efforts and will perform less than optimally.
Fitness specialists recomment that after a workout that depletes muscle glycogen (so after about one hour of higher intensity), you eat a meal composed of 3:1 carbohydrate:protein. When you do so, insulin and growth hormone levels rise, and testosterone levels fall. This boosts muscle building while at the same time maintaining healthy hormone balance. Cortisol levels appear to stay the same after you eat. For women, luteneizing hormone levels also stay the same . This demonstrates that it is not hormone levels in general that fall when you eat post-workout, but testosterone levels specifically.
Moreover, it seems as though post-work-out feeding reduces muscle soreness, too.
Testosterone is important for a lot of functions in the female body. Excess testosterone, however, is not. Excess testosterone causes infertility, poly cystic ovarian syndrome, acne, male pattern hair growth on the face and body, hair loss on the top of the head, and diminished libido.
Here are some summaries of papers I recenty read to demonstrate these effects:
Kramer, Volek et al 1998 compared the hormonal responses to consecutive days of resistance training with and without nutritional supplementation. Subjects drank either a carbohydrate‐protein supplement 2 hours before and immediately after their workout or a placebo. Blood was taken before and 0,15,30,45 and 60 minutes after the workout. Lactate, growth hormone, and testosterone were significantly elevated immediately postexercise in all subjects. Growth hormone and prolactin responses on day 1 were significantly higher for supplementing subjects, then leveled out. After exercise, testosterone declined below resting levels for supplementing subjects during all three days. Glucose and insulin remained stable for placebo subjects and were significantly elevated by 30 minutes during supplementation. Insulin‐like growth factor‐I was higher during supplementation on days 2 and 3, indicating long-term increases in IGF1.
Chandler, Byrne, et al 1994 examined the effect of carbohydrate and/or protein supplements on the hormonal state of the body after weight training exercise. Subjects consumed either a control (water), protein, carbohydrate, or carbohydrate‐protein drink immediately and 2 hours after a resistance training workout. Blood samples were drawn before and immediately after exercise and during 8 hours of recovery. Exercise induced elevations in lactate, glucose, testosterone, and growth hormone in all groups. Carbohydrate and carbohydrate-protein stimulating insulin levels. Carbohydrate‐protein led to an increase in growth hormone 6 hours post exercise which was greater than protein and control. Supplements had no effect on insulin‐like growth factor‐I but caused a significant decline in testosterone. Testosterone levels fell below resting levels 30 minutes postexercise during all supplement treatments compared to the control.
Many people deliberately fast after a workout in order to burn as much fat as possible.
While this is a reasonable approach for people who are significantly overweight or who do only this only occasionally, women who repeatedly fast after workouts can experience significant long-term testosterone elevations.
I used to be one of these women. My testosterone levels were through the roof…. but I was completely insulin sensitive. Conventional wisdom says that insulin is the primary means by which testosterone becomes elevated in the body (it directly stimulates testosterone production in the ovaries). Clearly, insulin wasn’t my problem.
I can’t say that my daily high intensity workouts and limited fueling were the only cause of my high testosterone levels. Most definitely they were not.
But it seems that they were a culprit. And I can honestly say that deliberately refueling after every workout (like with awesomeness that is Tanka bars!) and dance class, along with being sure to include plentiful carbohydrates in my diet, relax as much as possible, and gain a few body fat percentage points, has drastically improved my sex drive and the quality of my skin.
The healthiest athletes I know – and some incredibly beautiful female fitness competitors, to boot – always, always, always refuel after a workout.
THIS is my favorite post-workout snack, rich in protein and carbs with a little bit of fat… from grass-fed buffalos!
Check out more awesome snacks like smoked salmon, protein bars, and powerhouse paleo granola here.
Even if you are on a low carbohydrate diet, I — and low-carbohydrate gurus, too — recommend consuming some carbohydrates after your workout. Make it at least 30 grams of carbohydrate — so about two apples, or a half cup of rice — and 10 grams of protein, so 1-2 eggs, or half a can of tuna. Fasting after a workout very occasionally is okay. And it varies by individual. Nonetheless science doesn’t lie – a fasted workout decreases muscle growth, increases soreness, and elevates testosterone levels in women.
And, of course, for more on how to fast, and how many carbs and fat grams and the like to eat…
you can learn all about that in my book on weight loss for women Weight Loss Unlocked. To get a jump start on it, you can dowload a free chapter of the book HERE, and sign up for updates on more free weight loss tips and info!
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