By Dr Eathon Pekeur — Sports Medicine
How nicotine subtly impairs cardiovascular efficiency and limits performance—even in well-conditioned athletes
Performance in sport is measured in seconds—but lost in systems most athletes never see. At the centre of it all sits the cardiovascular system, quietly determining how much work the body can sustain.
It is often described as the engine of the body, and in many ways, that analogy holds. But like any engine, performance isn’t just about capacity. It’s about efficiency. In high-performance environments, even small inefficiencies tend to surface exactly when they matter most—late in competition, under fatigue, or during repeated efforts.
For that engine to function optimally, a few fundamentals need to be in place. Efficient oxygen exchange, healthy blood flow, and a cardiovascular system that can respond to demand without excessive strain allow output to remain controlled and repeatable. Just as importantly, the system must recover quickly—returning to baseline between efforts so it can produce again when required.
Oxygen delivery remains the primary limiting factor in sustained performance. Cardiac efficiency determines how much work the heart can perform without unnecessary strain, while vascular function governs how effectively blood reaches working tissue. When these processes are aligned, performance feels stable. When they are not, athletes often describe a sense of unexplained fatigue or inconsistency.
Most athletes don’t plateau from lack of effort. They plateau because something in the system is quietly inefficient.
The challenge is that performance does not always respond to what feels beneficial.
Nicotine is a clear example. It can increase alertness, elevate heart rate, and create a temporary sense of readiness. Research has shown short-term improvements in attention and reaction time (Heishman et al., 2018). In isolation, this can appear advantageous—particularly in sports requiring rapid decision-making or heightened focus.
The effect, however, is short-lived—and physiologically expensive.
Nicotine exposure is associated with reduced aerobic capacity, limiting the body’s ability to sustain prolonged effort. Vaping, often perceived as a safer alternative, has similarly been linked to lower cardiorespiratory fitness (Wills et al., 2021). These changes are not always immediately obvious but become evident under load, where efficiency is tested.
In addition, nicotine interferes with vascular function, impairing the ability of blood vessels to dilate appropriately during exercise (Qasim et al., 2017). This restricts blood flow to working muscles, reducing oxygen delivery precisely when demand is highest.
At the same time, increased sympathetic activation elevates heart rate and blood pressure, placing additional strain on the cardiovascular system (Moheimani et al., 2017). Over time, this shifts the system away from efficiency and towards compensation—where more effort is required to produce the same output.
In practice, these changes rarely present as overt dysfunction. Instead, they emerge as subtle warning signs under load—often easy to overlook, yet rarely insignificant. Athletes may demonstrate an elevated heart rate relative to workload, reduced tolerance to sustained effort, or a slower return to baseline between efforts. A disproportionate sense of fatigue, despite consistent training, is also common. Individually, these findings may appear minor. In combination, they point towards a system operating below optimal efficiency and should be interpreted with intent rather than dismissed as normal variation.
In elite sport, improvements are measured in small percentages. The same is true for decline.
“Athletes chase marginal gains relentlessly—yet often tolerate marginal losses without realising it.”
This becomes particularly relevant when comparing nicotine delivery methods. While vaping is frequently viewed as a lower-risk alternative to smoking, its cardiovascular effects remain measurable (Antoniewicz et al., 2019). The absence of smoke does not equate to the absence of physiological consequence.
Ultimately, if the cardiovascular system is the athlete’s engine, efficiency determines output. And in environments where seconds matter, nothing is neutral. Every input either sharpens the system—or quietly degrades it.
Author Bio
I am a sports medicine physician, co-founder of Sank-Med Medical Practices, and Chief Medical Officer of SPU Sport. My work focuses on performance optimisation and the integration of clinical practice, data, and applied sports science. I am currently leading efforts to establish the first high-performance centre in the Northern Cape.
References
Heishman SJ, et al. (2018)
Wills TA, et al. (2021)
Qasim H, et al. (2017)
Moheimani RS, et al. (2017)
Antoniewicz L, et al. (2019)