Condition category
Circulatory System
Date applied
12/12/2011
Date assigned
14/02/2012
Last edited
20/01/2014
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Contrary to high occupational physical activity (physical activity at work), leisure time physical activity and exercise are well known to prevent cardiovascular disease and enhance cardiorespiratory fitness. The reasons for such differences are not well known. Cleaners represent a group with high occupational physical activity and a high risk of cardiovascular disease.
The aims of the study is to find out whether the participation in an exercise at work in order to improve cardiorespiratory fitness can reduce the risk factors for cardiovascular disease or affect the cardiovascular workload among cleaners. The aim is also to assess whether such an exercise can be successfully implemented at cleaning companies, with high participation throughout one year.

Who can participate?
Cleaners of either gender aged 18 – 65 years old will be invited to participate through their company. Participants that are pregnant or suffering from cardiovascular diseases, other serious or chronic illness, severe trauma or frequent migraine will not be able to participate. Participants who are allergic to band aids will be excluded from daily measurements.

What does the study involve?
The participants will be randomly allocated to either exercise or lectures for the whole period of the study. Participation involve three health checks and daily measurements. Health checks include measurement of height, weight, fat percent, blood pressure, cardiorespiratory fitness and a blood sample. Daily measurements include four 24-hour measurements of heart rate and physical activity, and one 24-hour measurement of blood pressure.

What are the possible benefits and risks of participating?
Participants will gain extra knowledge regarding their own health through either the exercise or the lectures. There are no known risks when criteria for participation are followed.

Where is the study run from?
The study is managed from the National Research Centre for the Working Environment in Denmark, Copenhagen.

When is the study starting and how long is it expected to run for?
The project started in August 2011 and is anticipated to end in August 2014. The participating companies will be involved in the study for the duration of approximately 14 months.

Who is funding the study?
The Danish Working Environment Research Fund and University of Copenhagen (Denmark).

Who is the main contact?
Mette Korshøj Larsen

Trial website

Contact information

Type

Scientific

Primary contact

Mr Andreas Holtermann

ORCID ID

Contact details

Lersø Parkallé 105
Copenhagen
2100
Denmark
aho@nrcwe.dk

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

N/A

Study information

Scientific title

Cardiorespiratory fitness, cardiovascular workload and disease among cleaners: a cluster randomised worksite intervention

Acronym

Study hypothesis

Baseline measurements
1. Cleaners with high cardiorespiratory fitness have lower cardiovascular workload (% of heart rate reserve) than cleaners with low cardiorespiratory fitness
2. Occupational physical demands (i.e. cardiovascular workload and upper body work) are positively related to diurnal ambulatory blood pressure

The four months intervention with aerobic exercise will:
1. Increase cardiorespiratory fitness
2. Decrease diurnal ambulatory blood pressure
3. Improve self-rated work productivity
4. Reduce rate of perceived exertion (RPE) during work
5. Improve metabolic cardiovascular risk factors
6. Reduce the need for recovery

A one year aerobic exercise intervention will:
1. Sustain cardiorespiratory fitness from measurements after 4 months
2. Successfully result in high long-term participation

Ethics approval

Committees on Biomedical Research Ethics of the Capital Region of Denmark, 10 November 2011 ref: H-2-2011-116

Study design

Cluster randomised controlled trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Other

Trial type

Quality of life

Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet

Condition

Aerobic exercise for prevention of cardiovascular disease among cleaners.

Intervention

Participants will be randomised in clusters to receive one of the following interventions for one year. The clusters will relate to their work team where possible or groups where participants report to the same manager or work in close proximity.

Worksite aerobic exercise:
Supervised intervention at the worksite with aerobic exercise of 60 minutes duration parted in 2-3 weekly sessions are offered during the first four months of intervention. The amount of supervision is reduced during the last six months of the intervention, in which the participants are encouraged to continue with the exercise themselves.
The aerobic exercise will be aimed to be performed at an intensity of > 60% of maximal oxygen consumption. The types of aerobic exercise are tailored to the specific worksite through a modified intervention mapping approach, including organisation, leaders and employees.

Reference group:
Receives 5 lectures concerning healthy living during the one year intervention period; none of the lectures will address physical activity.

Intervention type

Other

Phase

Not Applicable

Drug names

Primary outcome measures

Cardiorespiratory fitness will be measured before the randomisation at baseline, after the 4 months intervention and after the 1 year intervention

Secondary outcome measures

1. Diurnal heart rate
2. Diurnal ambulatory blood pressure
3. Self-rated work productivity
4. RPE during work
5. Intensity and number of regions with self-rated musculoskeletal pain
6. High Sensitivity C-reactive protein (hsCRP)
7. High density lipoprotein (HDL)
9. Self-rated need for recovery
10. Participation in intervention

Measured before the randomisation at baseline, after 4 months intervention and after 1 year intervention

Overall trial start date

01/08/2011

Overall trial end date

01/08/2014

Reason abandoned

Eligibility

Participant inclusion criteria

Companies:
1. Cleaning companies (> 50 employees)
2. Implementation of project activities during working hours

Participants:
1. Working > 20 hours/week
2. Age 18 – 65 years old
3. Signed informed consent

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

120 participants

Participant exclusion criteria

Exclusion from physical tests:
1. Cardiac insufficiency
2. Acute myocardial infarction or acute coronary syndrome within the last few years
3. Hypertension (> 160/> 100 mmHg)
4. Serious or chronic illness
5. Severe trauma
6. Frequent migraine
7. Pregnancy
8. Fever

Exclusion from diurnal measurements:
1. Allergic to band aid
2. Pregnancy
3. Fever

Recruitment start date

01/08/2011

Recruitment end date

01/08/2014

Locations

Countries of recruitment

Denmark

Trial participating centre

Lersø Parkallé 105
Copenhagen
2100
Denmark

Sponsor information

Organisation

Danish Working Environment Research Fund (Denmark)

Sponsor details

Landskronagade 33
Copenhagen
2100
Denmark
+45 7012 1288
at@at.dk

Sponsor type

Government

Website

http://www.arbejdstilsynet.dk

Funders

Funder type

Government

Funder name

Danish Working Environment Research Fund (Denmark)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Funder name

University of Copenhagen (Denmark)

Alternative name(s)

University of Copenhagen, KU

Funding Body Type

private sector organisation

Funding Body Subtype

academic

Location

Denmark

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

1. 2012 protocol in http://www.ncbi.nlm.nih.gov/pubmed/22888833

Publication citations

  1. Protocol

    Korshøj M, Krustrup P, Jørgensen MB, Prescott E, Hansen ÅM, Kristiansen J, Skotte JH, Mortensen OS, Søgaard K, Holtermann A, Cardiorespiratory fitness, cardiovascular workload and risk factors among cleaners; a cluster randomized worksite intervention., BMC Public Health, 2012, 12, 645, doi: 10.1186/1471-2458-12-645.

Additional files

Editorial Notes