Supplements that may enhance performace

Genetics, physical conditioning, sport-specific training, periodized programs, mental health, recovery strategies, and nutrition are all primary factors for endurance athlete development and performance. Dietary supplements are a secondary factor with the potential to make a minor contribution to success. This week, I will summarize a different supplement each day with an adequate amount of scientific support to suggest potential competition gains. Please note: before adding any new supplement to your diet, it’s a good idea to consult with your doctor.


Maughan RJ, et al. IOC consensus statement: dietary supplements and the high-performance athlete. Br J Sports Med. 2018 Apr;52(7):439-455.

Peeling P, et al. Evidence-Based Supplements for the Enhancement of Athletic Performance. Int J Sport Nutr Exerc Metab. 2018 Mar 1;28(2):178-187.




caffeine is a stimulant which is rapidly absorbed into the bloodstream with well-established benefits for athletic performance such as improved endurance capacity


  • blocks adenosine receptors which in turn produces a stimulating effect
  • increases endorphin release leading to a positive feeling after exercise
  • improves neuromuscular function by activating the central nervous system
  • reduces perception of exertion


  • optimal dose of 3–6 mg/kg of body mass (BM), in the form of anhydrous caffeine (pill or powder), consumed about 60 minutes prior to exercise
  • lower caffeine doses of <3 mg/kg BM both before and during exercise may provide benefit
  • higher caffeine doses ≥9 mg/kg BM do not appear to increase performance

performance impact

  • enhanced endurance capacity such as exercise time to fatigue and time trials of varying duration (5–150 min), across numerous exercise modalities including cycling
  • low doses consumed during endurance exercise (after 15–80 minutes from the start) may enhance cycling time trial performance by 3–7%
  • 200–300 mg of caffeine at the 10-km point of a 30-km cycling time trial bout was shown to improve mean power output (+3.8%) during the final 10 km of the bout, in addition to a 4% increase in peak sprint power output at the end

additional interesting tidbits

  • a genetic variation that affects how you metabolize caffeine may determine the extent to which caffeine improves your endurance performance
  • due to its positive effects on exercise performance, some organizations, such as the National Collegiate Athletic Association (NCAA), have started to ban caffeine in high doses
  • both caffeine and caffeinated coffee produce similar benefits for endurance exercise performance
  • similar performance outcomes in both habituated caffeine users and nonusers

Nice. The very last bullet-point was surprising to me. I had read elsewhere that habituated users (I drink a lot of coffee every day, and have for many years) wouldn’t benefit, or would benefit substantially less. Of course I’m always already dosed with caffeine before riding, so presumably I’m already benefiting. Doing a rough calc, it looks like might increase that a bit. 3-6 mg/kg would be ~385 mg for me. I have some caffeinated gels that range from 20 to 100 mg of caffeine.

Oooo super useful, thanks @coach.jinger.g ! Could you do one each on Beta Alanine, Collagen and Creatine but with some specifics around benefits to women, know these might be different for us, particularly with BA?

It appears, and this does not contradict what @coach.jinger.g wrote, that caffeine does not actually interfere with sleep. The “reduces perception of exertion” does make you feel “awake”, and makes you feel that you do not need to go to, or cannot sleep.

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It also blocks the Adenosine receptors tho, which is what makes you wired. I can sleep when I am not fatigued. But I can’t sleep when I am exhausted but wired.


Great topic @coach.jinger.g ! Can’t wait to hear what else is coming up. While I enjoy a good coffee, I’ve never really used caffeine before a time trial, but may be something I’ll look into.

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I can’t take caffeine as it gives me heart palpitations. I drink tea and that is fine but even one can of red bull will send my heart into palpitations. This is quite common i think?

The recent data show that habituated users still benefit assuming they are genetically sensitive- And cool for an additional boost in mg!

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@DameLisa you may have guessed a few of my upcoming supplements!!! teehee And if there is specific research for women, I will include it for sure!

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Yes @Heretic ! slightly different effects- reducing perception of exertion and the stimulating effect…

True @ozmadman! Many individuals are genetically sensitive to caffeine and supplementation is detrimental-

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Thanks Coach! :grin::grin::grin:




creatine is a substance found naturally in muscle cells - it helps your muscles produce energy during high intensity exercise


  • about 95% of the body’s creatine is stored in the muscles, predominantly in the form of phosphocreatine
  • supplementing increases phosphocreatine stores and helps produce the high energy molecule, ATP


  • loading phase = ~20 g/day (divided into 4 equal doses of 5 g) for 5-7 days
  • maintenance phase = 3-5 g/day (single dose) for the duration of the supplementation period
  • concurrent consumption with a mixed protein and carbohydrate source (~50 g) may enhance muscle creatine uptake

performance impact

  • acute performance improvement of single and repeated bouts of high-intensity exercise
  • chronic training adaptations include lean mass gains and improvements to muscular strength and power
  • enhanced endurance performance resulting from improved protein synthesis, glycogen storage, and thermoregulation

additional interesting tidbits

  • no negative health effects are noted with long-term use (up to 4 years) when appropriate loading protocols are followed
  • after creatine loading there is a potential for 1-2 kg increase in body mass due to water retention which may be detrimental to endurance performance
  • some reports propose creatine supplementation to be anti-inflammatory, and to reduce exercise-induced oxidative stress
  • creatine supplements also increase phosphocreatine stores in your brain, which may promote brain health and improve symptoms of neurological disease

Great idea! This comes right when I thought supplements would make an excellent topic for the Knowledge podcast. Thank you for this topic and your comprehensible summaries.

Vitamin D is a big one. Provided you have it with a bit of fat to absorb properly. It’s like night and day when I have it for energy.

Iodine, Vitamin C, L-Citrulline, Copper, Zinc, Spinach (not a supp, but works pretty well)


@coach.jinger.g - are there drug interactions to be avoided with creatine?

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Can you share a few more details regarding your comment that caffeine supplementation may be detrimental to some individuals who are genetically sensitive? I, for example have CYP1A2 rs762551 = AC (medium metabolism), ADORA2A rs5751876 = CC, & HTR2A rs6313 = GG.

Using the chart in this research article, suggests I would need to go higher dosages for less gain, yet run the risk of it impacting sleep.

HI @Heretic - The reported contraindications are related to dehydration and kidney function. And while the risk is minimal if you want to try creatine and you are taking any of these medications, please talk with your physician first.

Non steroidal anti-inflammatory drugs (NSAIDs)

Taking creatine with these pain relievers may increase the risk of kidney damage. NSAIDs include ibuprofen (Motrin, Advil) and naproxen (Aleve).


Caffeine may make it hard for your body to use creatine, and taking creatine and caffeine may increase the risk of dehydration. Using creatine, caffeine, and ephedra (now banned in the U.S.) may increase the risk of stroke.

Diuretics (water pills)

Taking creatine with diuretics may increase the risk of dehydration and kidney damage.

Cimetidine (Tagamet)

Taking creatine while taking Tagamet may increase the risk of kidney damage.

Drugs that affect the kidneys

Using creatine along with any medication that affects the kidneys may raise the risk of kidney damage.


Taking creatine while taking probenecid, a drug used to treat gout, may increase the risk of kidney damage.

source: Mount Sinai


Hi @robyork! Looks like you have an interesting mix in terms of genetic sensitivity- there is still not a wealth of data on ADORA2A… but the data on CYP1A2 suggests that the higher end dose of 5-6 mg/kg may be beneficial without a detriment to your sleep. Have you experimented with dose and timing?

So you must use caution if you use creatine with the previous supplement you discussed, caffeine.