The Physical Activity and Population Health BJSM Blog Series

By Sonia Cheng @soniawmcheng

Gentlemen, if there was ever a reason to meet the physical activity guidelines, this is it. A systematic review and meta-analysis published in BJSM this year has suggested that physical activity interventions, particularly moderate-vigorous intensity aerobic activity, can improve erectile dysfunction.

Erectile dysfunction is the persistent inability to achieve or sustain an erection sufficient for satisfactory sexual performance¹, with prevalence rates ranging from 2% to 9% in men under 40 years and from 10% to 71% in men over 70 years². That’s an estimated 322 million cases worldwide by 2025³. And while we can certainly imagine how this sexual disorder might deteriorate quality of life, erectile dysfunction is also a predictor of future cardiovascular disease (CVD). In fact, it is often the first manifestation of endothelial dysfunction in men with underlying systemic CVD⁴.

The first-line treatment of erectile dysfunction is pharmacological therapy, but physical activity has increasingly been recognised as an important treatment and prevention strategy, mainly due to the improvements in endothelial function associated with regular moderate-vigorous intensity physical activity (MVPA).

It’s all about blood flow, baby

The penile erection is dependent on the release of nitric oxide, which relaxes the smooth muscle of the penile blood vessels and leads to the engorgement of the cavernous and spongy bodies⁵. In the presence of endothelial dysfunction, however, there is a lower availability of nitric oxide and thus impaired vasodilation in the penile vasculature.

Regular physical activity is thought to improve endothelial function by reducing oxidative stress and restoring the balance of vasodilator and vasoconstrictor substances production⁶, resulting in an enhanced availability of nitric oxide and – hopefully! – a happy ending.

The results of the systematic review

Seven randomised clinical trials of 478 participants with erectile dysfunction were pooled in the meta-analysis. There was a moderate-to-high risk of bias in the trials due to questionable assessor blinding, and the inability to blind participants and therapists due to the nature of the intervention. All seven trials used the International Index of Erectile Dysfunction (IIEF) to measure changes in patient-reported erectile function, and follow-up ranged from 8 weeks to 2 years.

Across the trials there was significant heterogeneity in the age of participants, the predisposing factors and severity of erectile dysfunction, and the type and dose of physical activity prescribed. Four trials involved a supervised exercise program, which varied from aerobic training, pelvic floor muscle training, to combined exercise interventions. Four trials combined the physical activity intervention with pharmacological treatment, while the remaining three evaluated physical activity without usual care.

Pooled data showed an improvement in erectile function score of 3.85 points (95% CI 2.33 to 5.37) following the physical activity intervention. This effect does not exceed the minimal clinically important difference (MCID) for erectile function score, which has previously been identified as 4 points⁷, but the MCID is known to vary widely according to severity of erectile dysfunction at baseline. Promising evidence indeed, that MVPA should be prescribed alongside pharmacological therapy to treat erectile dysfunction.

Only one of the seven trials, which included older functionally debilitated men with existing CVD, did not show a significant improvement in erectile function score⁸. The authors suggest that these participants were likely on medications (e.g. beta-blockers, diuretics) to manage their CVD, which can impact negatively on both erectile dysfunction and exercise tolerance.

And what about for women?

Perhaps unsurprisingly, the effects of physical activity on sexual function in women are relatively unexplored. Two small cohort studies of healthy middle-aged women have demonstrated associations between higher levels of self-reported physical activity and better sexual function on the Female Sexual Function Index^9,10. No trials have yet evaluated whether physical activity interventions improve sexual function in women.

The long and the short of it

So gentlemen, on days when the motivation to be physically active is in the realm of negative values, think back on this systematic review – the benefits you gain from regular physical activity may just carry over into the bedroom too.

Link to the full paper

Silva AB, Sousa N, Azevedo LF, et al. Physical activity and exercise for erectile dysfunction: systematic review and meta-analysis. Br J Sports Med 2017;51:1419–24.

Sonia Cheng graduated from The University of Sydney with a Bachelor of Applied Sciences (Physiotherapy) (Honours Class I) in 2014. Sonia is currently employed as a physiotherapist with Royal Prince Alfred Hospital and Westmead Hospital in Sydney. 

We invite you to share and support the Physical Activity and Population Health BJSM Blog Series. Join the conversation on ‘how change happens’ at #PAblogBJSM and #brightspotsBJSM. We welcome guest blogger contributions. If you have any ideas please email emmanuel.stamatakis@sydney.edu.au.

References

1. NIH Consensus Conference on Impotence. NIH Consensus Development Panel on Impotence. JAMA 1993;270:83–90.
2. Prins J, Blanker MH, Bohnen AM, et al. Prevalence of erectile dysfunction: a systematic review of population-based studies. Int J Impot Res 2002;14:422–32.
3. Ayta IA, McKinlay JB, Krane RJ. The likely worldwide increase in erectile dysfunction between 1995 and 2025 and some possible policy consequences. BJU Int 1999;84:50–6.
4. Kendirci M, Nowfar S, Hellstrom WJ. The impact of vascular risk factors on erectile function. Drugs Today 2005;41:65–74.
5. Burnett AL. Role of nitric oxide in the physiology of erection. Biol Reprod 1995;52:485–9.
6. Leoni L, Fukushima AR, Rocha LY, et al. Physical activity on endothelial and erectile dysfunction: a literature review. The Aging Male 2914;17:125–30.
7. Rosen RC, Allen KR, Ni X, Araujo AB. Minimal clinically important differences in the erectile function domain of the International Index of Erectile Function scale. Eur Urol 2011;60:1010–6.
8. Kalka D, Domagala Z, Dworak J, et al. Association between physical exercise and quality of erection in men with ischaemic heart disease and erectile dysfunction subjected to physical training. Kardiol Pol 2013;71:573–80.
9. Cabral PU, Canário AC, Spyrides MH, et al. Physical activity and sexual function in middle-aged women. Rev Assoc Med Bras 2014:60:47–52.
10. Dąbrowska J, Drosdzol A, Skrzypulec V, Plinta R. Physical activity and sexuality in perimenopausal women. Eur J Contracept Reprod Health Care 2010;15:423–32.