Evidence
Alert

High-intensity interval training rapidly improves fitness in patients awaiting surgery for urological cancer

High-intensity interval training (HIIT) significantly improved men’s fitness in the short timeframe before cancer surgery. A small study found that HIIT improved the heart and lung (cardiorespiratory) function of men with urological cancers such as of the prostate, bladder or kidney.

The authors hope their findings will lead to the development of effective exercise regimes for men with these cancers who are waiting for surgery. Patients with other types of cancer may also benefit from similar training.

What’s the issue?

Cancers of the prostate, kidney and bladder are common in the UK, with over 69,000 new diagnoses each year. Surgery carries a high risk of complications. Many patients struggle to get back to their former levels of physical ability, with a knock-on effect on their quality of life.

Clinicians are aware of the importance of optimising patients’ overall health before surgery. This multi-pronged approach is known as prehabilitation. Previous work has suggested that improving cardiorespiratory fitness before surgery reduces the risk of complications, increases quality of life after surgery, and improves long-term survival rates.

In the UK, the National Cancer Action Team states that initial treatment should take place within 31 days of the decision to treat. This leaves only a small window in which prehabilitation can take place.  

Previous studies have found that HIIT can improve the health of patients with certain cancer types over short time periods. However, within urology, most prehabilitation studies have focussed on reducing specific complications, such as urinary incontinence, rather than general fitness. 

This study aimed to assess whether HIIT could improve cardiorespiratory fitness within four weeks in patients with urological cancers awaiting surgery.  The authors examined the effect of HIIT on blood pressure, body composition, and muscle structure. Once the exercise regime was completed, patients were asked whether they enjoyed taking part.

What’s new?

This randomised controlled trial included 34 cancer patients over the age of 65 who were scheduled for major urological surgery.  Most patients completed between 10 and 12 HIIT sessions on an exercise bicycle in a university laboratory. Patients completed five bursts of exercise, each of one minute. They all achieved more than 85% of their maximum predicted heart rate during the sessions. They rated the exercise protocol as highly acceptable and enjoyable.

After 31 days, the authors identified a meaningful improvement in cardiorespiratory fitness for the patients taking part in HIIT, versus those undergoing standard care in the control group. The study reports improvements in:

  • the highest intensity exercise that can be sustained without lactate building up in the blood and causing muscle fatigue and pain (the anaerobic threshold)
  • the peak volume of oxygen  utilisation, a measure of aerobic fitness 

The authors also found:

  • a reduction in blood pressure (systolic blood pressure: -8.2 mmHg; diastolic blood pressure: –6.47 mmHg)
  • an increase in the fibre quality and thickness of the thigh muscle, vastus lateralis 

Why is this important?

Within a month, this HIIT regime improved cardiorespiratory fitness, cardiovascular health, and muscle condition. This makes the protocol a feasible prehabilitation tool in the 31-day target window between cancer diagnosis and treatment. 

Further research is required to assess patient outcomes after surgery. But  the authors suggest that the reported improvements in physical fitness could help reduce medical problems and deaths related to surgery and speed up patients’ subsequent recovery.

Comparing the results of this study with other prehabilitation exercise research suggests that HIIT could deliver greater improvements in fitness than other approaches such as walking and traditional aerobic exercise. 

The HIIT protocol followed here – carried out in a laboratory setting with a doctor present – is unlikely to be delivered in a real-world setting. The authors note that it may be difficult to ensure exercise intensity and compliance in unsupervised training.  

What’s next?

The authors hope that larger, randomised trials will provide firmer links between HIIT and improved outcomes after cancer surgery.  

Further research is also required to: 

  • examine the responses of other patient groups – including different age groups, patients who also have other conditions (comorbidities), and patients with other cancer types
  • establish optimal exercise methods 
  • work out how best to roll out HIIT to large numbers of patients
  • take into account dietary intake and habitual activity levels 

The study was part of a larger project, which is analysing muscle biopsy samples. This ongoing research aims to deepen understanding of the biological mechanisms behind the improvements reported here. 

You may be interested to read

The full paper: Blackwell JEM, and others. High-intensity interval training produces a significant improvement in fitness in less than 31 days before surgery for urological cancer: a randomised control trial. Prostate Cancer and Prostatic Diseases. 2020 (online ahead of print)

Principles and guidance for prehabilitation by Macmillan Cancer Support

Prehabilitation evidence and insight review by Macmillan Cancer Support

Conflict of interest

The authors have declared that no competing interests exist.

Funding

This research was supported by the NIHR Biomedical Research Centre in Nottingham. 

Commentaries

Study author

We have now studied a large number of older people in this and other studies within our unit using this HIIT protocol. We’ve seen rapid improvements in both anaerobic threshold and the peak volume of oxygen utilisation, even in patients with active cancer.

Most cancers result in inflammation and muscle and fat loss that are thought to blunt responses to training. Given this, it’s perhaps surprising that we saw that men with prostate cancer benefit as much as healthy volunteers of the same age.

There are a number of ongoing studies that provide prehabilitation exercise sessions in community gyms. We are investigating the effectiveness of unsupervised home-based activities, which may allow delivery to wider numbers if efficacy is proven.

James Blackwell, General Surgery Research Fellow, Royal Derby Hospital and the University of Nottingham School of Medicine

Researcher

This paper on its own is unlikely to result in changes to policy and practice. However, it provides the basis for future studies to address its follow-up questions. If those studies are equally positive, there is the potential for this exercise intervention to be implemented on a larger scale and have a positive impact on patient outcomes.

The next step will be to identify whether this improvement in fitness prior to surgery results in meaningful changes in outcomes after surgery, such as recovery of physical function, health-related quality of life, and work absence.

It will be important to establish if these findings are broadly translatable to other cancer patient populations and other participant groups, including women.

Richard Metcalfe, Lecturer in Sports and Exercise Sciences, University of Swansea