The runner\u2019s high, where pavement-pounding drudgery turns into something like a chemically enhanced experience, is an elusive state to pin down. Some people seem to get it during most of their runs; others rarely, or barely at all. A few lucky Couch to 5kers claim to experience it within their first few sessions, while some professional athletes doubt that it even exists. This is partly due to individual differences in brain chemistry, and partly because the way you train has a significant effect on how likely you are to experience it.<\/p>\n
If you\u2019re on the verge of throwing away your trainers, though, there\u2019s good news: runner\u2019s high is real, and there are ways to maximise your chances of experiencing it, even if you\u2019d rather hit the pool or the river than the trail. On your marks, then \u2026<\/p>\n
Let\u2019s start by tackling the common misconception that it\u2019s all about endorphins. \u201cThe runner\u2019s high seems to be caused by an orchestra of neurochemical changes across several brain systems, including the opioid system \u2013 of which endorphins are a part \u2013 and the endocannabinoid or eCB system,\u201d says Dr Daya Grant, a neuroscientist and mental performance consultant<\/a>. \u201cWhile endorphins are certainly involved, they don\u2019t seem to be the main drivers of the runner\u2019s high; that central role belongs to the eCB system.\u201d<\/p>\n Endocannabinoids can light up your brain \u2013 or at least it feels that way. Illustration: Jitendra Jadhav\/Getty Images<\/p>\n To explain this a bit more, endocannabinoids are essentially the body\u2019s internal version of the compounds found in cannabis, produced to help you manage pain and forget stressful events, and stop your brain cells getting overexcited to the point of damage. The eCB system wasn\u2019t discovered until the 1990s, after the idea of the runner\u2019s high was first discussed \u2013 which is the main reason the endorphins theory took hold. But more recent research (on animals<\/a>) suggests that endorphins cannot pass through the blood-brain barrier. Endocannabinoids can, and seem to be the main mechanism for crucial aspects of the experience.<\/p>\n \u201cEndocannabinoid levels increase during moderate to vigorous running efforts and stay elevated for approximately 30-45 minutes post run,\u201d says Grant. \u201cECBs are particularly involved in two key features of the runner\u2019s high: euphoria and anxiolysis, which is reduced anxiety. They\u2019re also involved with pain modulation, mood enhancement, stress resilience and altered time perception, the latter of which is also a key feature of the flow state.\u201d<\/p>\n This brings us to another key clarification: the flow state \u2013 most simply defined as the point at which we\u2019re fully immersed in an activity where our skills match the level of challenge we\u2019re experiencing \u2013 is technically a different thing from the runner\u2019s high. They often occur together, and seem to involve some similar changes in the brain \u2013 for instance, temporarily reduced activation in areas of the prefrontal cortex that deal with self-focused thoughts such as \u201cI\u2019m tired\u201d or \u201cI\u2019m probably not running fast enough\u201d. But they can also be experienced independently of each other, and occur as quite different sensations.<\/p>\n \u201cSometimes we have a sense that a runner\u2019s high needs to be a state of euphoria, whereas flow is more like the state where our body and mind feel at one, and we might be less aware of any fatigue or discomfort we\u2019re feeling,\u201d says Dr Trish Jackman, associate professor in sport and exercise psychology at the University of Lincoln. \u201cA big element of that is that you\u2019re performing at a level where you\u2019re being challenged, but not too far outside your comfort zone.\u201d<\/p>\n There are also other neurochemical changes to consider. Alongside eCBs, dopamine \u2013 sometimes known as the \u201cfeelgood\u201d hormone \u2013 increases during long runs, typically peaking around the 60-minute mark, enhancing our cognition and motivation. Norepinephrine, a hormone that drives our body\u2019s fight-or-flight responses, rises significantly as we approach our maximum anaerobic threshold (for instance, during interval training), helping you to stay focused and alert. Put together, all of these different effects can help us to feel good during all sorts of workouts \u2013 without the sort of crash you\u2019d typically expect from more external sources of stimulation.<\/p>\n Being in nature may accentuate the positive effects. Photograph: SerrNovik\/Getty Images<\/p>\n So why do we get the runner\u2019s high, and how can we maximise our chances of feeling it? \u201cOne theory is that the human brain might have evolved to reward us for productive effort \u2013 the kind that results in food, safety or social status \u2013 rather than simply physical exhaustion,\u201d says Dr Grant. \u201cOur ancestors had to persist through discomfort and fatigue in order to find food and shelter, and so it makes sense that our brain would evolve to reward us for a challenging effort that was necessary for our survival. In general, sustained, moderate-to-hard aerobic effort seems to trigger the runner\u2019s high most reliably. High-intensity interval training can produce the same neurochemical changes, but it won\u2019t always lead to the more subjective feelings of euphoria and decreased anxiety.\u201d<\/p>\n Other elements of the high are tougher to pin down. Norepinephrine, for instance, \u201cseems to be context dependent: it\u2019s higher when stress is high, such as during competitive races versus noncompetitive runs,\u201d says Grant. There\u2019s little real evidence that the location of a run amplifies the neurochemical effects, but exercising in nature has other well-documented benefits for psychological wellbeing, and is probably helpful for other reasons.<\/p>\n \u201cPersonally, I find treadmill running difficult, but some people really like it,\u201d says Jackman. \u201cOne benefit of running on trails is that there\u2019s an element of play that comes into it, that, as adults, we often don\u2019t experience \u2013 jumping over tree roots or navigating your way through rough terrain, which physically is really good for you.\u201d Making runs more challenging in this way (as opposed to speeding up or slowing down) might also help with accessing flow states \u2013 as can ignoring your planned pace and simply going with what feels manageable.<\/p>\n Karsten Warholm, just after winning gold for Norway in the men\u2019s 400m hurdles at the World Athletics Championships in 2017. Photograph: Patrick Smith\/Getty Images<\/p>\n At this point, it\u2019s also worth saying that the runner\u2019s high \u2013 or something like it \u2013 has been documented in cyclists<\/a>, while rowers have reported similar effects<\/a> (though that study suggests that endorphins are at play). One explanation for its rarity in other sports is that it\u2019s rarer for fair-weather athletes to achieve the sort of sustained, moderate-intensity efforts that make feeling the runner\u2019s high most likely \u2013 if you\u2019re putting in bursts of effort and then cruising, such as when you pedal hard to get up a hill and then freewheel down, you\u2019re less likely to get into the right zone. Similarly, if you\u2019re doing interval training, you might not hit the sweet spot for a proper runner\u2019s high, as you thrash yourself and then rest. One reason that some pro athletes rarely (or never) experience the state is that they\u2019re often working at the top-end speed or putting in lots of easy miles \u2013 often going too fast or too slow to really get into the zone.<\/p>\n So is there any evidence that regularly achieving a runner\u2019s high can help get us \u201caddicted\u201d to exercise? \u201cThere\u2019s certainly evidence that running can alter the structure of the brain over time \u2013 for instance, by increasing the volume of the hippocampus, which is involved with learning and memory \u2013 but I\u2019m not sure there\u2019s any direct evidence linking repeated runner\u2019s high episodes with changes in brain structure,\u201d says Grant. \u201cWhat I would say is that running, in general, builds our stress resilience. And when we repeatedly experience the runner\u2019s high, we may train our brain to associate the effort of running with that, which then enhances our motivation to keep running.\u201d<\/p>\n As for why some people never seem to experience the high at all, that\u2019s still a contentious question. One leading theory is that some people have enzymes that \u201cclear up\u201d the endocannabinoids<\/a> produced during exercise too fast for them to have a noticeable effect.<\/p>\n