Walking at a brisk pace, and the amount of time spent at this speed, may lower the risk of heart rhythm abnormalities, according to a team of researchers whose paper was published online today (16 April) in the journal Heart.

Examples of such abnormalities  include atrial fibrillation, tachycardia (rapid heartbeat) and bradycardia (very slow heartbeat). The findings were independent of known cardiovascular risk factors, but were strongest in women, the under-60s, those who were not obese and those with pre-existing long-term conditions.

The article is written by Pei Qin, who is based at the School of Health and Wellbeing at the University of Glasgow, and colleagues. Dr Qin and colleagues looked at the impact of different walking speeds while exploring the potential role of metabolic factors and inflammation, as well as risk factors, such as age, sex, obesity, smoking, alcohol intake, and pre-existing long-term conditions. 

They drew on 420,925 UK Biobank participants for whom walking speed data was available from questionnaire responses. The amount of time spent walking at different paces – derived from activity tracker readings – was available for 81,956 of them.

A slow pace was defined as walking at less than three miles an hour; steady/average pace as three-four miles/hour; and a brisk pace as more than four miles/hour.

The average age of the participants was 55; more than half (55 per cent) were women, and most (97 per cent) were White. Overall, 27,877 participants (just over 6.5 per cent) reported a slow walking pace; 221,664 (53 per cent) an average walking pace; and 171,384 (41 per cent) a brisk walking pace. 

During an average tracking period of 13 years, 36,574 (nine per cent) participants developed heart rhythm abnormalities: 23,526 atrial fibrillation; 19,093 other cardiac arrhythmias; 5678 an abnormally slow heart rate; and 2,168 ventricular arrhythmias (abnormal rhythms originating in the lower chambers of the heart). 

Make-up of participants

Participants reporting a faster walking pace were more likely to be men, and tended to live in less deprived areas and have healthier lifestyles. They also had smaller waists, weighed less, had better grip strength, and lower levels of metabolic risk factors, including blood fats and fasting glucose, as well as lower levels of inflammatory activity, and fewer long-term conditions.

After accounting for potentially influential background demographic and lifestyle factors, an average or brisk walking pace was associated with significantly lower (35 per cent and 43 per cent, respectively) risks of all heart rhythm abnormalities compared with a slow walking pace.

And these walking speeds were associated with lower risks of atrial fibrillation (38 per cent and 46 per cent, respectively); and other cardiac arrhythmias (21 per cent and 39 per cent, respectively) compared with those who reported walking at a slow pace.

Some 4,117 of the 81,956 participants with activity tracker data developed arrhythmias. Those who spent more time walking at a brisk pace were generally younger, more likely to be White and male, and live in less deprived areas. They generally had healthier lifestyles, and were healthier, overall. 

‘This study … provide[d] evidence that metabolic and inflammatory factors may have a role: walking faster decreased the risk of obesity and inflammation, which, in turn, reduced the risk of arrhythmia’ [Pei Qin et al]

While the amount of time spent walking at a slow pace wasn’t associated with the risk of developing heart rhythm abnormalities, more time spent walking at an average or brisk pace was associated with a 27 per cent lower risk.

Overall, around 36 per cent of the association between walking pace and all heart rhythm abnormalities was influenced by metabolic and inflammatory factors. 

The observed associations were independent of known cardiovascular risk factors, but were strongest in women, the under- 60s, those who were not obese, those who had high blood pressure and those with two or more long-term conditions.

Caveats and conclusions

As the study was observational in nature, Dr Qin and colleagues acknowledge that firm conclusions cannot be drawn about cause and effect. And they acknowledge that part of the study relied on self-report while the study participants did not reflect a broad spectrum of ages and ethnic backgrounds.

Dr Qin and colleagues note: ‘This study is the first to explore the pathways underpinning the association between walking pace and arrhythmias, and to provide evidence that metabolic and inflammatory factors may have a role: walking faster decreased the risk of obesity and inflammation, which, in turn, reduced the risk of arrhythmia.’

And they explain: ‘This finding is biologically plausible because cumulative epidemiological studies have shown that walking pace is inversely associated with metabolic factors, such as obesity, HbA1c [fasting glucose], diabetes, and [high blood pressure] which, in turn, are associated with the risk of arrhythmias.’

Fact file

• Heart rhythm abnormalities (arrhythmias) are common, note the authors, with atrial fibrillation alone doubling in prevalence over the past three decades to reach nearly 60 million cases worldwide in 2019.

• As these abnormalities are associated with heightened risks of cardiovascular disease, sudden cardiac death, and disability, pinpointing modifiable risk factors is essential to stave off the toll taken on health, they add.

• While walking pace is associated with lower risks of cardiovascular disease and death, few studies have looked at its potential impact on heart rhythm abnormalities.

To access the full version of the article – titled Association of self-reported and accelerometer-based walking pace with incident cardiac arrhythmias: a prospective cohort study using UK Biobank Doi: 10.1136/heartjnl-2024-325004 – see: https://heart.bmj.com/lookup/doi/10.1136/heartjnl-2024-325004

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