Last year a provocative paper by Professor Marcora suggested that psychoactive drugs could be used to help lazy people exercise.1 At the time of reading this paper I felt that the idea was ridiculous and completely unethical. Four months on, I’ve had time to reflect on the idea and now believe that it has some merit. Before I go on to talk about why I’ve changed my mind lets first revisit Samuele Marcora’s argument.
We are becoming a nation of overweight individuals, too many of us live a sedentary lifestyle feasting on processed foods dense in calories. However, while the obesity pandemic is obvious to everyone, current interventions to promote physical activity are failing.
Marcora argues that humans are inherently lazy and this makes total sense from an evolutional point of view. The so called sloth gene theory suggests that humans have evolved to conserve as much energy as possible to enable them to hunt for extended periods of time when necessary.2 However, now we don’t need to hunt as we can just drive down to the shops.
It’s instinctive for us to take the easy option, why take the stairs when you could take the lift? However, it’s not the actual activity itself that is difficult, rather the perceived effort. For example, the only way to reduce discomfort during exercise is to reduce intensity. However, for a nation of time poor and overweight individuals vigorous exercise has a clear number of benefits over low intensity exercise.3,4 With this in mind wouldn’t it be great if you could maximise the benefits of physical activity by making strenuous exercise more attractive to non-athletes.
Imagine if there was a drug you could take before every workout that reduced your perception of effort and discomfort without reducing the intensity or duration of the activity? Well, Marcora argues that the properties of psychoactive drugs mean that they have the potential to be used in this matter. Their ability to induce significant changes in mood and cognition means that they could reduce perception of effort and discomfort during exercise and facilitate greater exercise compliance.
This might sound like a dream, however many individuals are already using a psychoactive drug in their daily life to help them reduce the perception of effort and increase energy levels. That drug is caffeine.5 The positive effect on exercise performance is associated with caffeine’s ability to modulate cortical activity and reduce exercise induced muscle pain,3,5 resulting in a more pleasurable experience. Of course these benefits are only short lived and most of the caffeine studies have been conducted on physically active cohorts.
If we were to push this concept further. Marcora has identified methylphenidate (Attention deficit hyperactivity disorder drug) and modafinil (a drug used off label to reduce mental fatigue and sleepiness) as potential drugs that could aid exercise adherence. Both these drugs have been shown to reduce perception of effort and improve performance during vigorous exercise,6 while having few side effects.7 Marcora goes onto suggest that these drugs could be used independently or in addition to drugs that act on the opioid system to enhance the so-called “runner’s high”.6
In the future it is plausible to have a therapeutic regime that both reduces the perceived effort of exercise, along with increasing the reward, this would hopefully favour long term adherence to physical activity.
Marcora suggests that the insight to use drugs to improve public health in this manner may be restricted due to the negative connotations associated with performance enhancing drugs in sport. My initial reaction to this paper wasn’t induced by the potential of doping but rather society’s increasing attitude towards a quick fix. However, having time to reflect on this idea I feel my views at the time were apathetic.
Changing behaviour is extremely difficult and I feel it is often easy for athletic individuals to belittle the struggles many non-athletes have to maintain an active lifestyle. For many individual’s sport and physical activity wasn’t a constant in their up bringing. They weren’t members of sports teams and they didn’t regularly participate in physical exercise. These ‘non-athletes’ not only failed to experience the positive feelings associated with exercise but also didn’t have the opportunity to understand the body’s capabilities to endure the perceived efforts that are affiliated with physical activity.
For many of us it is easy to judge overweight individuals. However, adhering to a successful exercise routine would be like trying to learn a new language in adulthood. While, for a few this would be possible, however many of us would fail and soon give up. Imagine then if there was a drug that lowered the initial barrier of learning, until you were at a level where the perceived effort was manageable?
The current pandemic of physical inactivity and associated burden of disease are at a level were I believe we need to be open to medical interventions that could potentially increase physical activity. Professor Marcora published his ideas around the use of psychoactive drugs in helping to promote exercise in the hope that it would start a serious discussion surrounding the topic. I am not confident his argument will be considered a serious solution, however I do believe we have to be open to all ideas if we are to overcome obesity and sedentary lifestyles.
- Marcora S. Can doping be a good thing? Using psychoactive drugs to facilitate physical activity behaviour. Sports medicine. 2016;46(1):1-5
- Prentice M. Early influences on human energy regulation: thrifty genotypes and thrifty phenotypes. Physiol Behav. 2005;86:640–5.
- Gibala J, Little P, Macdonald J, et al. Physiological adaptations to low-volume, high-intensity interval training in health and disease. J Physiol. 2012;590:1077–84.
- De Morree M, Klein C, Marcora M. Cortical substrates of the effects of caffeine and time-on-task on perception of effort. J Appl Physiol. 2014;117:1514–23.
- Doherty M, Smith M. Effects of caffeine ingestion on rating of perceived exertion during and after exercise: a meta-analysis. Scand J Med Sci Sports. 2005;15:69–78.
- Motl W, O’Connor J, Dishman K. Effect of caffeine on perceptions of leg muscle pain during moderate intensity cycling exercise. J Pain. 2003;4:316–21.
- Jacobs I, Bell G. Effects of acute modafinil ingestion on exercise time to exhaustion. Med Sci Sports Exerc. 2004;36:1078–82.
- Battleday M, Brem K. Modafinil for cognitive neuroenhancement in healthy non-sleep-deprived subjects: a systematic review. Eur Neuropsychopharmacol. 2015 (in press).