Nicotine Increases Exercise Endurance

In my lectures on tobacco harm reduction I compare the properties of nicotine with those of caffeine (see slides at left).  Despite some obvious differences, the drugs have remarkably similar effects.  I have just found a study from 2006 showing that “…nicotine administration during moderate-intensity exercise delays fatigue, with a significant improvement of 17% [±7%] in time to exhaustion. This observation is similar to observations of the effects of caffeine supplementation.” (Available at the journal Experimental Physiology here).

Authors Toby Műndel and David A. Jones of the Human Performance Laboratory, School of Sport and Exercise Sciences, The University of Birmingham (United Kingdom), recruited 12 healthy non-smoking men and asked them to cycle in a laboratory setting at a moderate pace until exhausted on two occasions.  Subjects randomly applied either a 7 milligram nicotine patch or a placebo patch the evening before.  

Ten subjects who wore the nicotine patch cycled for 70 minutes – about 17% longer than the 62 minutes cycled by those with the placebo patch.  Nicotine had no effect on heart rate or respiratory parameters, and it “…did not alter the perception of effort… associated with progressive fatigue.”  The researchers noted that “…activity of dopamine pathways has

been suggested to be associated with improved endurance exercise performance.”  In other words, nicotine’s endurance boost stemmed from its effect on the brain. 

As I mentioned in 2011 (here), the World Anti-Doping Agency (WADA) is considering labeling nicotine a performance-enhancing drug.  However, WADA could treat nicotine as it has caffeine, summarized this way by the agency in 2012 (here):

“Caffeine was removed from the Prohibited List in 2004. Its use in sport is not prohibited.  Many experts believe that caffeine is ubiquitous in beverages and food and that reducing the threshold might therefore create the risk of sanctioning athletes for social or diet consumption of caffeine.  In addition, caffeine is metabolized at very different rates in individuals.”

Since using nicotine is a “social” choice and the substance is metabolized at very different rates, one can only hope that WADA applies such a reasoned, practical analysis to it as well.

Nicotine Improves Cognitive Performance

Six months’ treatment with nicotine produces measurable improvement in patients with amnestic mild cognitive impairment (MCI), a decline in cognition and function that falls short of dementia or Alzheimer’s Disease, according to research published in the journal Neurology (abstract here) by Dr. Paul Newhouse at the University of Vermont and colleagues at Vanderbilt, Georgetown, Duke and the University of California San Diego.

Newhouse et al. enrolled 74 non-smoking subjects and gave about half of them 15 mg. nicotine patches for six months (the other half got placebo patches). The results:

“This study demonstrated that transdermal nicotine treatment for 6 months improved cognitive performance in subjects with amnestic MCI…Several secondary cognitive measures showed significant nicotine-induced improvement including psychomotor speed and attention on several tasks as well as significant effects on long-term memory seen in both the paragraph recall task and computerized word recall task…There were trends for improvements in a number of other cognitive measures…There was no evidence for loss of cognitive effects over time. The primary clinical outcome, the Clinical Global Impression by the clinician, did not show significant improvement; however, patients and their informants did report nicotine-induced improvements.

“This study found that transdermal nicotine over 6 months is a safe treatment for nonsmoking subjects with MCI…measures of attentional, memory, and psychomotor performance did show an effect of nicotine and this finding provides strong justification for further treatment studies of nicotine for patients with early evidence of cognitive dysfunction.”

This study extends the results from previous reports. According to Newhouse et al.:

“Cognitive improvement is one of the best established therapeutic effects of nicotine (PubMed Reference here). In human studies, nicotine improves performance in smokers on cognitively demanding attentional tasks (References here, here and here). In clinical studies, memory improvement was initially seen with IV nicotine in subjects with Alzheimer’s Disease (Reference here). Others have also found nicotine administration by subcutaneous injection or transdermal patch to improve
cognitive function in Alzheimer’s Disease (References here, here and here; one reference not in Pubmed).”

This research confirms that nicotine improves cognitive performance in people with MCI, and it may also benefit those with Alzheimer’s Disease. For those who would demonize nicotine, this should be highly informative.

International Sports Monitoring Agency: Nicotine, Smokeless Tobacco May Enhance Performance

The World Anti-Doping Agency (WADA), an international agency composed and funded by sport organizations and governments, on September 27 announced it will “monitor the effects nicotine can have on performance when taken in oral tobacco products such as snus,” starting in 2012 (here). This followed publication of a report from the agency’s laboratory on over 2,000 urine samples from athletes in 43 sports. The report, by François Marclay and colleagues at the University of Lausanne in Switzerland, is abstracted here.

The research measured exposure to and active use of nicotine by athletes. While the prevalence of active use was only 15%, the authors noted high prevalence in some sports, included in this table:

Active Nicotine Consumption Among Athletes
Sport (No. of samples)	Active Consumers (%)
American football (19)	56
Basketball (24)	25
Biathlon (38)	18
Bobsleigh (38)	31
Football (soccer) (205)	19
Gymnastics (48)	29
Ice hockey (108)	32
Rugby (25)	28
Skating (41)	20
Skiing (143)	26
Volleyball (46)	20
Wrestling (31)	32

Marclay wrote that these results provide “alarming evidence” about nicotine consumption among athletes. But the report had no information about the athletes who were tested, and the number of samples was minuscule. For example, Marclay’s claim that 56% of American football players actively used nicotine was based on only 19 samples. There are over a million football players at the high school level in the U.S., thousands at the college level, and hundreds in the NFL, and there are 18 other countries with American football leagues. The most alarming aspect of this report is that it made sweeping claims based on very little evidence.

Marclay wrote that “…smokeless tobacco is a very attractive drug from a doping perspective, considering the performance enhancement pharmacological properties of nicotine and the absence of direct adverse effects on the respiratory tract.” Nicotine “exhibits a variety of pharmacological properties sought-after by consumers,” and it “results in vigilance and cognitive function enhancement together with relaxation, reduced stress, mood modulation and lower body weight.”

These effects are well known among tobacco users, but Marclay cited no authority for the claim that these properties enhance performance to an extent that justifies prohibition in sports. In fact, Marclay acknowledged that “the frontier between recreational consumption and use for doping purpose is difficult to ascertain with social drugs, including nicotine, caffeine or tetrahydrocannabinol (THC)[marijuana].” Would Marclay and WADA ban caffeine along with nicotine?

In trying to tie smokeless tobacco to performance enhancement, Marclay offered a startling non-sequitur: “Since smoking may be responsible for noticeable respiratory effects and numerous health threats detrimental to sport practice at top level, likelihood of smokeless tobacco consumption for performance enhancement is a hypothesis of very serious concern.” Simply put: Smoking is very bad, so smokeless tobacco must be a performance enhancer. The association of these two very different products in this manner defies logic.

Marclay was especially concerned about athletes involved in winter sports. Citing his own work (abstract here), he wrote that “a recent study on the 2009 Ice Hockey World Championships brought alarming findings as active nicotine consumption before or/and during the games was highlighted for about half of the athletes.”

If WADA rules eventually that smokeless tobacco and nicotine enhance athletic performance, it will refute tobacco prohibitionists’ persistent claim that tobacco provides no tangible benefits to consumers. As I have written (here), “It’s time to be honest with the 50 million Americans, and hundreds of millions around the world, who use tobacco. The benefits they get from tobacco are very real… It’s time to abandon the myth that tobacco is devoid of benefits, and to focus on how we can help smokers continue to derive those benefits with a safer delivery system.”