Hey Endurance Athletes, Want Your Testosterone Back?

It’s no secret that endurance training can lead to reductions in testosterone. Theories behind the reduction of testosterone during endurance training previously revolved around the loss of body mass, increased cortisol levels, and changes in luteinizing hormone. However, there is some debate around this, and the mechanism is not 100% clear. Nonetheless, the reduction of testosterone can have a mildly negative impact on recovery from training and a big impact on your quality of life.

Drops in testosterone can result in decreased libido, mood changes, decreased energy, and prolonged recovery from workouts. There are several more symptoms, however these are the most relevant to endurance athletes.

Testosterone decreases appear to be correlated to the amount and intensity of training. The general rule of thumb is, the longer you train each week, the lower your testosterone level. Interestingly, resistance training, such as lifting weights, increases testosterone, while endurance training decreases testosterone. Research has yet to answer some questions regarding this difference. If I may throw in a completely subjective opinion, I will say that when something like this occurs naturally, there is typically a reason, and that reason is protective against a detrimental consequence. However, for now we must work with the body of evidence we have, and that appears to suggest that lower testosterone negatively affects performance.

Testosterone supplementation and hormone replacement is banned in sports. Yes, even for amateurs. Of course, some discretion should be used here. If you are a middle of the pack age grouper without a shot at placing within your age group, your relationship with your wife is hurting because of decreased libido and mood, and you are struggling to be as productive as you should be around the house because of your lower energy, well, the answer of what to do seems obvious. But, cases like this have not been addressed by USADA yet, and the substance is simply banned in sanctioned events. However, if you are a top age grouper, I would strongly advise you against even considering testosterone, unless you may qualify for a therapeutic use exemption (no, “my wife wants me to go on testosterone” does not qualify you for an exemption). Recent evidence has found a high incidence of “cheating” among master’s and age group athletes, and testing on this population is likely to become routine in the future for top age group finishers. In fact, it has already started. Pro’s don’t even stand a chance, they will be caught.

Fortunately, there are interventions that may increase testosterone naturally. Here are some of the most effective.

  • Strength Training – adding in a day or two a week of strength training is one of the most effective ways to boost testosterone. If you can keep the intensity high that can further enhance the effects. Do intense 1-2 minute bursts of weight lifting.
  • Zinc – zinc is one of those “tricky” micronutrients in endurance athletes. It is involved in several important pathways that tend to be “used in excess” during training. Therefore, it is often lower than normal in endurance athletes. Zinc is important in testosterone production. Studies show that zinc supplementation may increase testosterone levels. On a related note, if you supplement iron at any point in your training (and if you do make sure you read my blog post about this), this can cause a reduction in zinc absorption, and thus a decrease in testosterone production. Zinc should be supplemented during iron supplementation. Supplementing zinc at low levels is generally recommended for endurance athletes training more that 8 hours per week.
  • Reduce Sugar Intake – testosterone levels decrease after eating sugar. Diets high in sugar have been associated with reduced testosterone levels in some small studies.
  • More “relations” – having “relations” more frequently increases testosterone levels. Kind of a catch 22.
  • Eat Fats – fats are essential to testosterone production. This includes both healthy fats (avocados, fish oils) and saturated fats (yep, the ones we have been told are terrible for us all of these years). Studies show that increased fat intake may be correlated to increased testosterone. Now you have an excuse to eat bacon one day a week!
  • Eat eggs – egg intake is shown to increase DHEA-S, which in turn leads to more testosterone.
  • Get enough protein – endurance athletes should at least consider supplementing whey protein during peak training. This should be considered on an individual basis. However, most athletes could benefit from this, and it can help maintain higher testosterone levels.
Written on June 30, 2016
By Garret Rock

Antioxidants and Endurance Athletes

Antioxidants. From athletic performance and anti-aging to heart disease prevention and cancer treatment, antioxidants are touted as key components to fighting disease and optimizing wellness. Once considered the “fountain of youth”, these powerful, free radical fighting nutrients truly are amazing. They fight oxidative stress, a process that leads to cellular degradation and even cell death.

Following their discovery, antioxidant supplements quickly found their way into endurance sports, and have been a mainstay supplement ever since. They are touted for their anti-inflammatory effects in athletes, their ability to offset free radicals, and aid in recovering from training sessions. There is a large body of research on antioxidants for endurance athletes. The conclusions are nothing short of…well, completely confusing.

And so, I figured I’d write a post covering a few important points about antioxidants as they relate to endurance athletes. But first, some fun facts about antioxidants…

Antioxidants are most abundant in nature in fruits and vegetables. Antioxidant is a generic term for a nutrient or organic chemical that combats oxidative stress. There are many different antioxidants, and several different “types”. Three major types are micronutrients, enzymes, and phytochemicals (which include polyphenols). Well known micronutrient antioxidants include vitamins A, C, and E, and CoQ10. Many enzyme and phytochemical antioxidants are unnamed. Thousands of different ones have been identified, and thousands more are thought to exist. These too are found abundantly in fruits and vegetables.

And now for some important notes about antioxidants as they relate to endurance athletes…

Yes, antioxidants do benefit endurance athletes. They have shown in legitimate research to decrease perceived exertion in endurance athletes during exercise, significantly reduce muscle soreness and inflammation following workouts, and significantly decrease oxidative DNA damage. However, our approach of isolating antioxidants in highly concentrated supplements may not be as effective as we once hoped or suspected. As is almost always the case, nature’s delivery method is far more effective than ours.

I have made the comment in past posts that I believe we will one day find out that the enzymes and phytonutrients present alongside antioxidants in nature are integral to making certain nutrients absorbable and useful to their full potential. Most supplements do not contain the enzymes and phytonutrients, which are often lost in processing. A couple recent studies came to this conclusion. In one study, supplemental vitamins C and E showed no reduction in markers of oxidative DNA damage, however the authors found that in those individuals studied that had a higher intake of fruits and vegetables, decreased oxidative DNA damage was noted. In the other study, researchers studied the effects of a powdered fruit/vegetable juice concentrate versus supplemental vitamins C and E. They found that although the powdered juice concentrate had much less vitamins C and E, the antioxidant effects were significantly greater. They concluded this to be related to phytonutrients, which remain present in some powdered fruit/vege juice concentrates and whole food supplements (Cancer Epidemiol Biomarkers Prev 2000; 9(7): 647-52 and Med Sci Sports Exerc 2006; 38:6, pp1098-1105).

Antioxidant supplementation may not be all good news, however. There are a couple very important considerations for endurance athletes. The first is that some polyphenols appear to inhibit iron absorption (Penn State 2010, August 23, Polyphenol antioxidants inhibit iron absorption). As an example, green tea, which is known to be high in polyphenols, has been shown to inhibit iron absorption. This is a big deal, as iron is the key micronutrient for red blood cell production and function (see blog post on red blood cell turnover). It is also a micronutrient that has a high turnover rate in endurance athletes. Supplementing iron blindly (aka without monitoring blood levels) is generally considered to be a poor decision, as an overabundance of iron in the system is linked to several serious health problems, including cancer risk (see my blog post on supplementing iron for more information). Therefore, it is important to be aware of the relationship between polyphenols and iron, and thus pay attention to where you are getting your antioxidants. Avoid the polyphenol sources, and stick with the fruits and veges ideally. Interestingly, Vitamin C, a powerful antioxidant, enhances iron absorption. The second consideration is that over-supplementing antioxidants (levels not established) may actually elicit a pro-oxidative effect, which is the opposite of the desired anti-oxidative effect. In addition, some recent research suggests that completely inhibiting post-exercise inflammation may be detrimental to recovery.

So, in summary, yes, supplementing antioxidants appears to be beneficial, however the form of the supplement matters. Research continues to support combination antioxidant supplements, such as those containing a combination of vitamins A, C, E, and selenium. However, powder or whole food supplemental forms of antioxidants appear to be superior. But, the most effective form is through eating lots of fruits and vegetables. The key in supplementing is to keep it in moderation. Unfortunately, we don’t know how much is too much yet, hopefully this will be established soon.

My recommendation, get a Vitamix (or akin) and fill it with fruits and veges of many different colors each day. Have a fruit smoothie for breakfast. Eat lots of salads. Do these things and you will get plenty of unadulterated, wonderfully bioavailable antioxidants that are partnered with their enhancing phytonutrients and enzymes. If you just can’t make this happen, reach for the supplements (of the type mentioned above), because they do appear to work, just keep it in moderation by sticking to the recommendations on the bottles.

Written on
By Garret Rock

Athlete Thermoregulation: Tips for Keeping Cool When It’s Hot


Thermoregulation is the ability of an organism
to maintain a body temperature within certain boundaries, even when the
surrounding temperature is very different. Basically, this refers to your ability
to stay warm in cool environments, and cool in hot environments. A
physiological example of thermoregulation is sweating.
The concept of thermoregulation is important to
endurance athletes because it directly correlates to performance. The inability
to control temperature swings results in a decrease in performance, and can put
an end to your race day altogether. This decrease in performance is hardly
negligible, just look at the following statistics from a study on marathon
  • In elite pro runners, for every 5 degrees over 41
    degrees Fahrenheit, times slow by 0.4%. On a 77 degree day, an elite
    pro will expect to run 5% slower than on a 41 degree day.
  • The rate of slowing increases with slower run times.
    For example, in this study, they found that a 3 hour marathoner will be
    around 12% slower on a 77 degree day compared to a 41 degree day. This
    brings their finish time from 3 hours flat to 3 hours 21 minutes.
Fortunately, there are small steps we can take
to battle the performance deficits that come with hot temperatures. Here are four
of the most effective methods for avoiding over-heating during training and
Hydration is your first line of defense in
thermoregulation. Although on the surface hydration seems simple, how you
hydrate and what you hydrate with can actually have a big impact on
thermoregulation and hydration status.
Laboratory based tests conclude that
hyperhydration is an effective strategy for maintaining a slightly lower body
temperature during endurance exercise in hot temperatures. Hyperhydration, put
simply, is preventatively taking in fluids, or drinking when you are not
thirsty. This effect seems to be due to a faster onset of sweating and improved
“sweating efficiency”. For shorter races (1-3 hours), hyperhydration
does appear to be an appropriate strategy on a hot day. Exactly how effective
this strategy is in improving performance is yet to be determined at these
distances, but theoretically benefits do exist, as research definitely shows
improved thermoregulation through hyperhydration.
One way to enhance hyperhydration without having
to chug down as many bottles of water is to nutritionally optimize
intracellular fluid uptake. One supplement that aids this is glycerol, yep that evil alcohol sugar. Before undertaking glycerol supplementation for hyperhydration, be sure to do your research, or better, work with a professional that knows what they are doing. Done right, you win. Done wrong, you lose. In addition, during exercise,
plain water is fairly poorly absorbed in the intestines. Including
carbohydrates in a fluid replacement drink is crucial for optimal fluid
absorption in the intestines. In fact, research shows that combining a
carbohydrate with water during exercise improves intestinal fluid absorption up to
six times!
Action Step: I recommend using a sports
drink as your primary hydration source always.
On exceptionally hot days, I recommend drinking 25 ml/kg body weight (175 lb
person will drink approximately three 21 oz bottles) of fluids prior to the
race. Make two of them water and one a sports drink. Be sure to use electrolyte tabs as
directed during the race to ensure adequate electrolyte levels. 
There is not much science to be found on the
effect of water dousing on core temperature during exercise, however anecdotal
“evidence” strongly supports frequent water dousing during a race in
the heat. Fortunately, many races in hot environments now provide sponges and
cups of ice for dousing.
Action: At each aid station be sure to douse yourself
with water and/or ice/sponges. This is typically only needed during running, as
the wind during biking is typically enough to evaporate sweat quickly.
Your choice of clothing impacts thermoregulation.
Sweating is the body’s natural cooling method. However, in order for sweating
to be effective, the sweat must evaporate. It is the evaporation of sweat that
cools the body. The ideal clothes for training and racing in hot weather allow
for air to flow through them. On sunny days, protecting the skin from the sun
is beneficial to staying cooler. Sunscreen can interrupt both sweat production
and evaporation. Although dark colors do absorb more heat when the sun is out,
in a short race this is unlikely to result in hotter core temperatures.
However, in a long race, opting for the lighter color is likely the wiser
decision. On sunny days, wearing a visor to protect from the sun and save on
sunscreen use is the wiser choice.
Action: In a running race, wear light, loose clothing.
If the sun is out in force, choose light colors. In a triathlon or cycling
race, choose a kit made of breathable material. Choose coverage with the light apparel over sunscreen for most of your body. 
On hot days, pre-cooling appears to mildly
improve performance in endurance races. For long and ultra races (Ironman,
70.3) this may not provide much performance enhancement. However, in shorter
duration races (marathons, half marathons, 10K’s, 5K’s, sprint tri’s, and
olympic tri’s), pre-cooling appears to benefit performance and thermoregulation
on hot days. Pre-cooling may include staying cool in the water prior to a
triathlon (if chilly), wearing a cooling vest during your warm up (www.stacoolvest.com), or sitting
in a cool environment. Basically, be chilled just prior to the race. But don’t
neglect an appropriate muscle warm up.
Action Step: Either
perform your pre-race warm up in a cooling vest, or perform your pre-race warm
up, then find a cool environment to sit in and get chilled (air conditioned car, water for a triathlon, or building close by). Being you’ll be sweating, the cool air will evaporate
the sweat well and result in rapid cooling.
Questions?  Contact us at results@athletebloodtest.com.  You can also shop our Panels at: http://www.athletebloodtest.com/our-test-panels/

Michael N. Sawka; Lisa R. Leon; Scott J. Montain; Larry A. Sonna
Integrated physiological mechanisms of exercise performance, adaptation, and maladaptation to heat stress 
Comprehensive Physiology 2011;1(4):1883-1928.

Eur J Appl Physiol Occup Physiol. 1987;56(5):603-7.

Thermoregulation in hyperhydrated men during physical exercise.

Grucza R, Szczypaczewska M, Kozłowski S.


Department of Applied Physiology, Polish Academy of Sciences, Warsaw.
Br J Sports Med. 2006 April; 40(4): 320–325.


doi:  10.1136/bjsm.2005.022426


Core temperature and hydration status du
ring an Ironman triathlon

P B Laursen, R Suriano, M J Quod, H Lee, C R Abbiss, K Nosaka, D T Martin, and D Bishop
Written on
By Garret Rock

Triathlete Training Podcast Interviews Garret Rock About Blood Monitoring for Endurance Athletes

I recently was a guest on the Triathlete Training Podcast (www.triathletetraining.com), where I was interviewed on blood monitoring for the endurance athlete. We discuss why, what, how, and when.

Simply hit play on the mini player shown just above to listen. Enjoy!

Here is the preamble from the Triathlete Training website:

Blood Monitoring

Garret Rock joins the show.  Garret is an exercise physiology specialist and Doctor of Chiropractic and sports nutrition specialist.  He does blood testing for both age group and professional triathletes.  He has done over 800 blood tests on professional triathletes.

His services are available through fiftyonespeedshop.com and he works at South Pointe Clinics in Colorado.  He charges roughly $120-$170 per analysis.

During the interview he gives an example of work he has done with Liz Blatchford. Liz finished third at Ironman Hawaii in 2013.  Over the course of several weeks Liz made the following changes in her blood measurements:

Test #1
2 Weeks Later
10 Days Later
3 Weeks Later
Liz was feeling fine when she had her first blood test, but Garret noticed a folate deficiency. With his help, which included some creative smoothie recipes that included beets and other not-so-tasty ingredients, Liz was able to make significant improvements in her hemoglobin and hematocrit levels.
Written on
By Garret Rock