Their bodies are working harder to accomplish the same task.
A generation that inherited warnings about cigarettes has quietly taken up a newer habit, and science is now measuring what that choice costs the body. Researchers at Manchester Metropolitan University have found that young adults who vape show roughly 15% lower fitness capacity than peers who have never used nicotine — a gap indistinguishable, in physiological terms, from that of cigarette smokers. Published in ERJ Open Research amid the UK's landmark 2026 Tobacco and Vapes Act, the findings arrive as a reminder that novelty does not equal safety, and that the body keeps its own honest accounting.
- Young people who vape cannot push as hard during exercise as their non-using peers — their lungs, hearts, and muscles are measurably falling behind.
- Inflammation in blood vessels and faster lactic acid buildup mean vapers experience breathlessness and leg fatigue that mirrors what cigarette smokers endure.
- The urgency deepens because many of these young vapers never smoked — they began with vaping itself, making harm reduction arguments irrelevant to their situation.
- Europe's youth vaping rates are climbing toward a quarter of teenagers, and genetic damage linked to lung cancer risk is already appearing in the data.
- The UK's 2026 Tobacco and Vapes Act now has physiological evidence behind it, and researchers are moving toward MRI studies to map the structural damage to hearts and muscles.
A study published this week in ERJ Open Research delivers a clear and uncomfortable finding: young adults who vape are significantly less fit than those who have never used nicotine. Researchers at Manchester Metropolitan University tested 75 healthy people aged 18 to 30 — divided equally into never-users, smokers, and vapers — putting them through incremental cycling tests while measuring heart, lung, and muscle responses. The groups were otherwise matched for lifestyle. The results were not.
Both vapers and smokers showed roughly a 15% drop in peak oxygen uptake compared to never-users. Their lungs struggled to clear carbon dioxide. Lactic acid built up faster in their muscles, arriving sooner and in greater quantities, producing more breathlessness and leg fatigue at the same workloads. Ultrasound and blood work confirmed inflammation in the blood vessels of both groups. Dr. Azmy Faisal, who led the study, was direct: vaping produces harmful changes to vascular and respiratory function during exertion that closely mirror those caused by smoking.
What makes the findings particularly pointed is who is vaping. Many of these young adults never smoked — they came to nicotine through vapes alone, with no prior habit to quit. Dr. Stamatoula Tsikrika of the European Respiratory Society noted that while vapes carry lower concentrations of carcinogens than cigarettes, they still trigger genetic damage and inflammation associated with lung cancer risk. For people who would otherwise have remained nicotine-free, she said, the trade-off is increasingly difficult to defend.
The study lands alongside the UK's 2026 Tobacco and Vapes Act, which restricts vaping product sales to minors and signals a broader policy shift. With 22% of European 15- to 16-year-olds reporting vape use, researchers see the physiological data as essential grounding for that legislation. Next, they plan MRI studies to examine how vaping reshapes the heart, lungs, and skeletal muscles at a structural level. For now, the cycling tests have already spoken plainly.
A study released this week in ERJ Open Research has found something straightforward and troubling: young adults who vape perform worse on exercise tests than their peers who have never touched nicotine products at all. The difference is measurable and significant. When researchers at Manchester Metropolitan University put 75 healthy young people through incremental cycling tests, they discovered that both vapers and smokers showed roughly a 15% reduction in overall fitness capacity compared to those who had never used either product.
The study design was careful. The researchers divided their 75 participants—all between 18 and 30 years old—into three equal groups: never-users, cigarette smokers, and people who had been vaping for about three years. All had normal lung function at rest. All reported similar lifestyles in terms of physical activity, caffeine intake, and alcohol consumption. The playing field was level. Then they made them work.
During the cycling tests, researchers measured how the heart, lungs, and muscles responded to increasing exertion. They took ultrasound images of the arteries and drew blood samples to assess inflammation. What they found was consistent across both the vaping and smoking groups: at peak exercise, oxygen uptake dropped by about 15%. The lungs struggled to expel carbon dioxide efficiently. Lactic acid accumulated faster in the muscles, arriving sooner and in greater quantities than in the never-user group. The result was predictable—more breathlessness, more leg fatigue, less capacity to push hard.
The ultrasound and blood work revealed inflammation in the blood vessels themselves. Dr. Azmy Faisal, who led the research, framed the finding plainly: vaping produces harmful changes to blood vessels and lung efficiency during exertion, much like smoking does. For young people who consider themselves active and healthy, the impact is immediate and measurable. They cannot perform at the level their peers can. Their bodies are working harder to accomplish the same task.
The timing of this research matters. The United Kingdom passed the Tobacco and Vapes Act in 2026, which bans the sale of vaping products to anyone under 18 and aims to reduce vaping among young adults more broadly. Faisal noted that the study provides evidence for policymakers and the public about early risks, particularly for the growing number of young people who have never smoked but have taken up vaping. They are not using it as a tool to quit cigarettes. They are starting with vaping as their first nicotine product.
Dr. Stamatoula Tsikrika, an expert on tobacco and smoking control at the European Respiratory Society, emphasized the broader concern: vaping is becoming normalized behavior among youth, and it may function as a gateway to nicotine addiction. While vapes contain lower levels of cancer-causing substances than cigarettes, they still trigger genetic damage and inflammation linked to increased lung cancer risk. For people who have never smoked, she said, the health consequences are becoming harder to justify.
The numbers underscore her point. In Europe, 22% of 15- to 16-year-olds report using vapes. Ninety-four percent of smokers start before age 25. The UK's generational sales ban represents, in Tsikrika's view, a significant step toward protecting young people's health. The Manchester study provides the physiological evidence for why that protection matters. Researchers are now planning MRI studies to understand the deeper mechanisms—how vaping changes the heart, lungs, and skeletal muscles at a structural level. For now, the message from the exercise tests is clear: vaping carries real, measurable costs to young people's physical capacity.
Citas Notables
Both vapes and tobacco smoking led to worsened exercise capacity, shortness of breath, and intense leg fatigue in active, healthy young adults.— Dr. Azmy Faisal, Manchester Metropolitan University
Vaping is becoming normalised behaviour, functioning as a gateway to nicotine addiction and introducing serious health risks.— Dr. Stamatoula Tsikrika, European Respiratory Society
La Conversación del Hearth Otra perspectiva de la historia
Why does a 15% reduction in fitness matter for someone in their twenties who feels fine?
Because it's a marker of something happening inside the body that isn't visible yet. The inflammation in blood vessels, the reduced oxygen uptake—these are early warning signs. At 25, you might not notice it. At 45, you might.
But these are active, healthy young adults. Couldn't they just be less fit because they vape, not because vaping made them less fit?
The study controlled for that. All three groups had similar activity levels and lifestyles. The only variable was the nicotine product. So the difference in performance is attributable to the vaping itself, not to how much they exercise.
What's the mechanism? Why does vaping do this?
The study doesn't fully explain it yet. That's why they're doing the MRI work next. But the inflammation in the blood vessels suggests the nicotine and other chemicals in vapor are triggering an inflammatory response. That inflammation restricts blood flow and oxygen delivery to muscles during exercise.
Is this reversible? If someone stops vaping, does their fitness come back?
The study doesn't address that. It's a snapshot of people who have been vaping for about three years. Whether the damage is permanent or recoverable is an open question.
Why is the UK banning vapes for under-18s but not adults?
The act restricts sales to under-18s and aims to reduce use among young adults, but it's not an outright ban for adults. The concern is that vaping is becoming a first nicotine product for people who never smoked. For adults, the calculation is different—some use it to quit smoking. For kids, there's no benefit argument.
Does this study prove vaping is as bad as smoking?
It shows similar effects on fitness and blood vessel function in young people. But smoking has decades of research showing cancer risk, heart disease, and other long-term harms. Vaping is newer. This study is evidence that it's not harmless, but we don't yet know the full scope of long-term damage.