Aim: The purpose of the study was to establish noise levels to which fitness instructors are exposed to during the teaching of their classes, in particular when amplified music was used to motivate participants. The study also surveyed instructors to find out possible factors that may explain why such noise levels are being used in their classes.
Methods: An empirical study was performed using personal noise dosimetry to measure the noise levels and exposure of the fitness instructors at work. The exercise classes targeted where those which used pre determined amplified music. Five male and two female instructors from six gyms participated in the study. The study administered an after-class questionnaire to the instructors to ascertain the extent of the instructors’ workloads, awareness of noise, regulations and other factors.
Results: The lowest measured Equivalent Continuous Sound Level (Leq) was 81 dB (A) and the highest leq reading was 95 dB (A). The mean Leq for all the instructors was 88 dB (A). The lowest measured peak noise level was 128 dB (A) and the highest peak level was 144 dB (A).
The dosimeter equipment used was able to calculate the personal daily exposure level (Lep’d). Lep’d measurements ranged from 76 dB (A) and 85 dB (A) with a mean personal daily exposure of 80dB (A). The results showed that four (57%) of the instructors music levels were above the first action value in the Noise at Work Regs 2006 and two of those over the second action value.
None of the instructors sampled had received training in regard to hearing protection or controlling the nose levels within their classes. However, one instructor was aware of the Control of Noise at Work Regs, despite recording the second highest Lep’d of 84dB (A).
Conclusions: The study showed that there was no training and a poor awareness of the risks of exposure to high noise levels, with the majority of instructors exposing themselves to such risks frequently. There is a need for education and training for both the instructors and the gym management.
Chapter One Introduction 1.1 BackgroundNoise is a sound that produces undesirable physical or psychological effects (Cone and Hayes, 1985). The European Agency for Safety and Health at Work (EASHW) (2005) define noise as an unwanted sound, whose intensity is measured in decibels (dB), a logarithmic scale, which is A-weighted to take the human ear’s sensitivity into account. The EASHW (2005) estimate that during 2003/4, an estimated 80,000 people in Great Britain thought they were suffering from a hearing problem that was caused or made worse by their previous or current occupation. Similar research by the Medical Research Council survey in 1997-98, gave a prevalence estimate of 509 000 people in Great Britain suffering from hearing difficulties as a result of exposure to noise at work (Palmer et al, 2001).
The Health and Safety Executive (HSE) defines that exposure to noise over 85 dB (A) through an 8 hour day is hazardous to hearing. This is further backed up by previous study performed by Jons (1996), which claims that 103,000 workers have deafness, tinnitus or other ear conditions which is associated to their employment and that a further 18,300 have a condition made worse by their work.
Employees whose occupation lies within a noisy environment are more likely to suffer hearing loss and associated factors. Although many occupations involve noise, Diaz and Pedrero (2006) identified that people typically perform a range of activities throughout the day in varying locations, and subsequently exposed to a diverse range of sound environments. The EASHW (2005) highlight the issue that, millions of European workforce are subjected to noise at work, and that while noise in the industrial sector are an obvious problem; it can also be an issue with a wide range of other working environments.
While Noise Induced Hearing Loss is most prevalent among individuals over the age of 65, the incidence rate is expected to rise as the population ages; the number of young people with hearing loss is increasing (NIOSH, 1998). This argument was concurrent with a study performed by Palmer et al (2002) who found that the prevalence of hearing loss and tinnitus increased with the extent of work-related exposure to noise, despite age increases.
The findings from previous studies present the possibility of clinical implications for those regularly attending fitness classes which includes pre set amplified music. This factor is increased as this noisy environment forms part of everyday life for instructors. Clinical implications of a noisy work environment include illnesses such as tinnitus and its associated consequences.
The health effects of noise on hearing have long been established. Maassen et al (2001) propose that numerous years of exposure to music with frequencies particularly damaging to hearing at high noise levels can lead to substantial damage and employees in a noisy workplace have an increased risk of hearing loss. A common consequence of excessive noise exposure is tinnitus. Tinnitus refers to a perception of noise arising without corresponding auditory stimulation (Baguley, 2002). This poorly understood condition is experienced by 10% 15% of the population at some time during their lifetime (Andersson et al, 2000). Many people experience symptoms shortly after exposure to loud noise, whereas other it can last until medical intervention. Tinnitus is often described as a ‘‘buzzing in the ears,’’ however it sufferers also describe the nose as whistling, hissing, ringing or roaring of varying intensity, loudness, and pitch. (McKenna, 2008). Sufferers of this disease may also find it difficult to distinguish between different sounds within their proximity, which can cause further discomfort.
The effect of tinnitus on an individual is not limited to a physical implication, but rather psychological, which include depression amongst other similar debilitating diseases (Andersson et al., 2005).
It has also been suggested that links between an increase in workplace accidents which may have involved excessive noise and hearing impairment (Picard et al, 2008).
1.2 AimThe aim of this dissertation is to establish noise levels and the potential adverse effects to which fitness instructors are exposed to during the teaching of their classes, in particular when amplified music is used to motivate participants. The study will also survey instructors to find out possible factors that may explain why such noise levels are being used in their classes.
1.3 Objectives Empirically identify the levels of sound used by fitness instructors during their classes Survey fitness instructors’ instructors’ to find out their knowledge of noise issues, amount of exposure and awareness of noise levels. Identify the workload of instructors and any other factors that may affect results e.g. hobbies. Analyse data Determine if factors outlined in the questionnaire have any consequence on the outcome of the measurements taken from the dosemeter. Identify findings and discuss problems encountered Discuss further research needs Chapter Two Literature Review 2.1 Noise Induced Hearing Loss (NIHL)The issue of NIHL has long been established, particularly within the manufacturing, mining, construction and foundry industries (William R, 2007). Hearing conservation programmes have been running throughout Europe, which in Sweden resulted in a drop of 3 dB (A) within the industrial machinery industry over a 20 year period (WHO, 1997)
The problem of leisure time NIHL may have first been recognised with the introduction of personal stereos. Various studies identified that it was not only the workplace that posed a risk to hearing, but also leisure times activities. Potential sources of high leisure noise levels include machinery (e.g. lawn mowers, power tools), rock concerts and discotheques, personal stereo systems and toys (Davies and Fortnum et al, 1985).
Despite the improvement in NIHL within the workplace and within some leisure environments’, it has mainly been limited to the workforces which fall within the industrial sector. NIHL is a recognised problem within the U.K and has been attempted to be addressed by the Control of Noise at Work Regulations 2005, however there are working environments which continue to be exceed recommended noise action values for example the noise which are experienced during an aerobics class (Nassar, 2001). While attending an aerobics class is unlikely to induce hearing loss, previous research suggests that regular exposure to noise over 85 dB (A) may be detrimental to hearing capabilities.
2.2 Noise in fitness classesThe use of amplified music in fitness classes is commonplace, primarily to motivate the participants and enhance fitness performance (Howley & Franks, 2007). It is also suggested that the use of music during fitness classes improves the performance of participants, and often noisy environment are necessary for the enjoyment of the activity. This is called the “social noise phenomenon” (Clark & Calvert, 1991). Also in this workout environment, young adults who participate in fitness classes are at risk of exposure to high levels of music delivered through loudspeakers (Yaremchuk & Kaczor, 1999). With the use of loud music in fitness classes, the risk of impairing instructors hearing increases, especially if they are exposed to the noise for prolonged periods of time. A fundamental detail of fitness instruction is the requirement for instructors to instruct participants as to exercises they’ll be performing and to offer encouragement. “Instructors often find themselves shouting commands to participants, which may result in vocal fold abnormalities. To overcome the strain of shouting over music, some instructors will use microphones that are louder than the background music. Unfortunately, this allows music to be played at an even louder volume” (Yaremchuk & Kaczor, 1999)
Previous research into the noise produced at fitness classes have concentrated on the level of noise within the room, rather than the instructors’ individual exposure. The Yaremchuk & Kaczor (1999) study measured sound pressure levels during aerobics classes at five different health clubs, readings were taken using a portable sound level meter.
A study of noise in fitness classes undertaken by Fusco and Marcondes (1989) was performed on numerous fitness classes in Sao Paulo, Brazil, recording noise levels ranging from 82dB(A) to 160dB(A). This study focused on the noise that was observable in the room and not the personal exposure of the instructors.
Palma et al (2009) performed a cross sectional study of 15 instructors in Brazil to identify the level of exposure that instructors were exposed to during the teaching of fitness classes and its relationship with other factors of health. Palma et al (2009) also used a questionnaire with to establish correlations between health factors and noise levels. To achieve sound pressure measurements, the study used a Sound Level Meter that was located near to the instructor to achieve a realistic personal dose measurement. The study found sound pressure levels ranged from 74.4 dB (A) and 101 dB (A) with a mean Leq of 89.81.
Wilson and Herbstein (2003) examined how participants in these aerobics classes perceived the music levels. Approximately, 75% of participants reported that the music was at a comfortable level when it was presented at both 85 and 89 dBA; and even when the level presented was 97 dBA, 67% of participants still felt that it was a comfortable level. Furthermore, 76% of participants enjoyed the class more when the music was presented at a level of 89 dBA. And finally, 74% of participants reported that they were more motivated to work harder when the music was presented at 89 and 97 dBA. An unfortunate consequence of enjoying a class more and being more motivated when the music is presented at such high levels is the potential deleterious long-term effects on hearing sensitivity.
A study performed by Yarenchuk and Kaczor (1999) measured noise levels at 5 different leisure centres and 125 aerobics classes. The study used a sound level meter to record sound pressure levels at 5 minute intervals, the study recorded a range of 78 dB(A) to 106 dB(A) and a mean Sound Pressure Level (SPL) of 94 dB(A) and 27 classes having an SPL of 90 dB(A).
Echoing the results found by Yarenchuk and Kaczor 2001, a study by Mirbod et al (1994) within 3 health clubs, found similar peak, and mean values within fitness classes.
A study into noise at aerobics classes in Manchester was performed by Nassar (2001), the study recorded noise levels in fitness class studios. The study by Nassar (2001) recorded a mean noise level of 89.6dB (A) and also performed a pure tone threshold hearing test based on the audible range of the class noise frequency (subjects). The subjects then attended aerobics classes. A noise level of 90 dB(A) was pre-set and the classes lasted 60 minutes, two minutes after the class had ceased, post class pure tone audiometry was performed. The study results showed that there was evidence of temporary threshold shift which has the potential to lead to permanent hearing loss (Moller, 2010). However, despite these findings, the use of pure tone audiometry to assess the potentially harmful effects of noise on people’s hearing has failed to show any marked effect in numerous studies (Carter, 1984).
2.4 LegislationThe Health and Safety at Work Act 197 general duties state that; It shall be the duty of every employer to conduct his undertaking in such a way as to ensure, so far as is reasonably practicable, that persons not in his employment who may be affected thereby are not thereby exposed to risks to their health or safety.
With particular relation to noise, there is further guidance on controlling noise levels within the workplace. The Control of Noise at Work Regulations 2005 are based on a European Union Directive, the Council and Parliament Directive 2003/10/EC of 6th February 2003, which stipulated the minimum health and safety requirements regarding exposure of workers to the risks arising from physical agents (noise) (HSE, 2006).
Regulation 5 of the regulations requires employers to perform a risk assessment for employees should their work activities expose them to noise at or above the lower action values mentioned in Regulation 4 (HSE, 2006). The intention of risk assessments is to identify hazards, decide who may be harmed, evaluate risks and decide on precautions, record finding and implement them and finally review and update them. In performing a risk assessment of noise exposure, it allows the employer to prevent and implement sufficient control of noise levels.
Further to this; Regulation 9 of the Control of Noise at Work Regs 2006 require that, where a risk assessment has identified a noise source which poses risk to an employee’s health, that hearing protection must be provided (HSE, 2006)
Regulation 10 of Control of Noise at Work Regs requires employers to supply employees with training and instruction should they be exposed to noise levels that breach the lower action values (HSE, 2006).`
An uncomplicated way towards the reduction of hazardous noise levels and compliance with the noise regulations in fitness classes would be to reduce the level of noise to a safe limit which reduces the risk of NIHL. This would result in safer working conditions, less strain on the vocals of instructors and reduction in noise related illnesses e.g. Tinnitus.
Within the Control of Noise at Work Regulations (2005), regulation 4 states the exposure limit values and action values as so:
Regulation 4.—(1) the lower exposure action values are
(a) a daily or weekly personal noise exposure of 80 dB (A-weighted); and
(b) a peak sound pressure of 135 dB (C-weighted).
(2) The upper exposure action values are—
(a) a daily or weekly personal noise exposure of 85 dB (A-weighted); and
(b) a peak sound pressure of 137 dB (C-weighted).
(3) The exposure limit values are—
(a) a daily or weekly personal noise exposure of 87 dB (A-weighted); and
(b) a peak sound pressure of 140 dB (C-weighted).
Chapter Three
Methodology 3.1 MethodAs already mentioned, there have been many studies into the noise levels within the fitness class arena, however, very few have been performed within the U.K and considered the personal exposure of instructors using a dosimeter.
This study will use a cross sectional method by recording personal exposure of instructors, using a dosemeter and questionnaire to identify the knowledge and awareness of instructors of noise issues, that may occur during their fitness classes.
The empirical study was performed over 7 different fitness instructors, teaching various classes within 6 different arenas within Hambleton District and Leeds. Initially 8 leisure centres were identified to participate in the study; however one of them refused to take part. Once permission had been granted by the management of leisure centres, Instructors were approached and explained what the study entailed and its aims outlined. Seven fitness instructors were approached, all of whom agreed to participate. The profile of instructors was varied and included inexperienced and experienced, male and female instructors.
The fitness classes chosen to participate in the study were based on the involvement of music to which the class was taught. The post class questionnaire was given to instructors to complete should they feel comfortable doing so. It was also explained to them that should they reverse their decision for the information on the questionnaire to be used, they could contact me and data would be destroyed. Participants of the fitness classes took no part in the study, and at times explained what the equipment the instructor was doing. This explanation was at the instructors’ discretion.
Due to instructors having to wear equipment and take time to participate in the study, it was decided that the instructor would only be asked to participate in the study once. Although this limited the length of the study, it was felt that this would be least problematic for instructors’ and management of gyms who may have felt uneasy at numerous reading being performed.
They types of classes were noise measurement were performed were, aerobics, boxercise, spinning and body attack. (See appendices for individual descriptions)
As with the nature of aerobics, movement is ongoing throughout the duration of the class, and using a sound level meter would not accurately record personal noise levels accurately. A dosemeter (Casella’s CEL-360 noise dosimeter) was used to measure the noise levels from the amplified music rather than a sound level meter as it provided a more accurate reading of the instructor’s personal exposure to the noise. The Dosemeter was be attached to the instructors clothing, as near to the ear as possible to get the most realistic measurement. Unlike a sound level meter, the use of a dosemeter will also taken into account how near the instructor is to the amplified music, consequently giving a more realistic measurement.
Prior to the commencement of the study and before each class, the dosemeter was calibrated and configured as to provide readings of Equivalent Continuous Sound Level (Leq), daily personal exposure (Lep’d), The dosemeter was also set to a (A) weighting to reflect the frequency response of the human ear.
The Dosemeter was calibrated and configured prior to each class begging and set to record minutes before the class began. This did not affect recording as the music in all classes was present prior to the class beginning its warm up. The dosemeter was locked for the duration of the class to limit accidental interference by the instructor. The dosemeter was then positioned on the hip of the instructor with a wire connected to the microphone which clipped on the neck of the instructors t-shirt, approximately 12cm from the ear. On completion of the class, the dosemeter was taken from the instructor and recordings stopped.
On completion of the class, instructors were asked to complete a questionnaire accompanied by an ethical information sheet as required by Leeds Metropolitan Universities Ethics Policy. It was decided to keep the questionnaire to one side of A4 due to time constraints of instructors and the likelihood of it being completed accurately. All instructors completed the questionnaire.
Recorded noise levels were taken from the dosemeter and given a reference number to allow correlations from questionnaire and recording to be analysed.
The post class questionnaire sought to identify the profile of instructors and their experience teaching classes. This included Age, Gender and experience of teaching fitness classes to music. These factors were included as a study by Daniel (2007) defined that risk factors for NIHL include age, gender and race, with age having the most significant factor of developing NIHL due to hearing capability declining with age. The experience of instructors teaching classes was asked to try identify whether through experience, noise levels decreases or due to continuous exposure noise levels increases due to poorer hearing.
The questionnaire also aimed to identify the knowledge of instructors regarding hearing damage, training of noise levels and the use of hearing protection and awareness of Control of Noise at Work Regulations 2006. These factors were chosen as they have not been included in previous studies and was felt that it would provide a indication of reasons why loud music if used. A final question of instructors opinion of the loudness aimed to identify their knowledge of what level of continuous noise exposure may induce hearing loss may sound like.
3.2 EthicsAll participant of the study were provided with written information sheets explaining the nature of the study in conjunction with a verbal explanation and questionnaire. Due to the free lance nature of instructors, written permission to perform the study was also sought prior to the study commencing (See appendix). All participants had the opportunity to withdraw the data collected. Participant data was kept confidential and secure, although it should be noted that names of participants were not kept attached to questionnaires.
Chapter Four Results 4.1 Study ResultsFor raw data that will be discussed in this section, see appendix 2.
Seven instructors agreed to participate in the study, all of whom completed the questionnaire and did not request to withdraw the data collected. One leisure centre refused my request to undertake the research. This level of full participation was expected due to the use of convenience sampling.
The socio demographics of the participants was as follows: 5 male (71.5%) and 2 female (28.5%). Two instructors were between the ages of 18-25 (28.5%), 3 Instructors were between the ages of 26-35 (43%) and 2 Instructors over the age of 36 (28.5%).
All instructors taught between 1 and 4 different types of class each week which involved amplified music. These were a combination of aerobics, spinning, boxercise and body combat. Of the classes mentioned; two instructors taught only boxercise (28.5%). Two instructors taught aerobics and spinning classes only (28.5%) and the remaining 3 instructors taught all 4 different classes during one week (42.9%). The results showed that body combat was the least taught class amongst instructors.
The number of hours a week teaching classes was split into two groups. Four instructors spent less than 10 hours a week instructing classes (57.14%) with remaining instructors teaching classes more than 10 hours per week (42.86%).
The experience of teaching classes varied greatly which generally had an impact on the number of classes they taught each week. Three Instructors’ had instructed classes for less than 2 Years (42.9%). Two instructors had instructed classes between 2 and 10 years (28.5%) and the remaining two instructors had taught classes for over 10 years (28.5%). The study found that the longer the instructor had been teaching classes, the more hours were spent each week instructing classes to music.
The perception of noise within classes varied from instructor thinking the music was quiet to loud. One instructor thought the music in their class was quiet (14.7%). Four instructors thought the noise level was ‘about right’ (57.14%) and the remaining two instructors thinking the music being played was loud (28.5%).
Of all the instructors surveyed, none had received training on the noise regs, with one instructor having an awareness of regulations. Despite one instructor reporting previous medical problems with their hearing, they had not received training or were aware of the Control of Noise at Work Regulation 2006. However, this person did perceive the music they were using as quiet,
4.2 Noise levelsThe lowest measured Equivalent Continuous Sound Level (Leq) was 81 dB (A) and the highest leq reading was 95 dB (A). The mean Leq for all the instructors was 88 dB (A). The lowest measured peak noise level was 128 dB (A) and the highest peak level was 144 dB (A).
The dosimeter equipment used was able to calculate the personal Daily Exposure Level (Lep’d). It was assumed that the rest of the day was quiet. This enabled the calculation of Lep’d measurements ranging from 76 dB (A) and 85 dB (A) with a mean personal daily exposure of 80dB (A). The results showed that four (57%) of the instructors music levels were above the first action value in the Noise at Work Regs 2006 and two of those over the second action value. Despite the remaining results recording values below the first action value, it must be noted that they still achieved a Lep’d no lower than 77 dB (A).
In relation to gender it was not possible to distinguish a trend in the results due to the small sample size that only included two female instructors.
The instructors that spent less than 10 hours a week instructing fitness classes to aerobics recorded a mean Lep’d of 77dB (A). Instructors teaching classes over hours a week recorded a mean Lep’d of 81.6 dB (A). A particular concern was of one instructor who was instructing classes to music for more than 35 hours per week, 6 days a week who recorded a Lep’d of 84 dB(A), this instructor also thought that the level of music being used in their class was not loud. Similarly, three other instructors whose Lep’d was above the first action value within the Control of Noise at Work Regs 2006, also did not think that level of music being used was loud.
The intention to use peak action values to analyse results was not possible due to accidental interference from the instructor to the microphone. This is evidenced by the particularly values of over 141 dB (A). This level of peak action value is not corresponding with noise levels within the fitness class environment.
None of the instructors had received training with regard to hearing protection or controlling the noise levels within their classes. However, one instructor was aware of the Control of Noise at Work Regs, but despite this recorded the second highest Lep’d of 84dB (A).
The study found that the second highest daily exposure of the instructors was of an instructor over the age of 36, with a Lep’d of 84 dB (A). The mean Lep’d for over 36 years olds was 81 dB (A). This theme continued as the study found that 3 of the 4 highest Lep’d recordings was amongst the 26 – 35 year olds, with a mean Lep’d of 80 dB (A). The 18 – 25 year old instructors recorded the lowest Lep’d of 73.5 dB (A). The results show that the older the instructors, the higher the mean Lep’d.
Table 1. Data obtained from questionnaires and recorded measurements from dosimeter.
Name Gender Age Years instructing Hours spent instructing Trained in noise regulations Medical problem Noise regs awareness Perception of noise level LEQ Lep’d 01 M 26-35 1 year 3 hours No No No About right 90 80 FC/02 M 18 – 25 3 Years 1 Day 4.5 hours No No No Loud 81 71 FC/03 M 36+ 10 years 3 Days 6 hours No Yes No Quiet 88 78 FC/04 M 26-35 16 years 6 Days 35+ hours No No Yes About right 95 85 FC/05 F 26-35 6 months 2 Days 4.5 hours No No No About right 89 80 FC/06 F 18-25 4 years 3 days 12 hours No No No Loud 85 76 FC/07 M 36+ 2 Years 4 days 10 Hours No No No About right 95 85 MEAN 89 79.5
Graph 1
Graph 2
Graph 3
Chapter Five Discussion 5.1 Noise exposureThe measurements that were measured included noise levels, peak noise levels, and daily exposure levels (Lep’d). This study found that the mean measured noise levels within different fitness classes to be 80 dB (A) based on a working day. This result was not unexpected as other studies have found similar noise levels within fitness classes. Although other studies have included more instructors, and their exposure to noise levels, they have concentrated on the levels of noise within the class alone and not the instructors themselves. This study used personal dosimetry to provide an accurate, life like measurement of noise levels within the classes. It also questionnaire considered the exposure of instructors based on their weekly teaching schedule. It also considered variable factors including age, lifestyle choices and awareness of regulations to determine if an association can be correlated (See appendix). The mean daily noise exposure value found by this study is in breach of the first action value set out by the Control of Noise Regulations 2005, Regulation 4. The findings clearly highlight an issue of excessive noise levels being used by instructors, however, due to the small convenience population used, it is difficult to generalise findings.
The mean daily exposure value found by the study may be an underestimation as it assumes that the rest of the day is quiet. The questionnaire highlighted that many of the instructors taught multiple classes each day, assuming similar noise levels were used in those classes. This is likely to affect the daily noise exposure of instructors resulting in an increased Lep’d. The mean Lep’d found in this study is particularly worrying for instructors who are instructing fitness classes over 10 hours per week. The study found that 3 instructors taught over 10 hours a week. This number of hours teaching at high levels of noise is likely to increase their daily noise exposure value and without intervention, increase the likelihood of Noise Induced Hearing Loss (NIHL).
The study confirmed that high levels of noise are being used in fitness classes to motivate participants to the detriment of their hearing. The problem is particularly concerning for instructors who are teaching multiple calluses per week. Due to the likely underestimation, it is likely that in actual fact the daily exposure would be higher and furthermore detrimental and in further breach of regulations.
An observation of the study was that instructors that used lots of loud verbal encouragement to participants resulted in higher daily noise exposure values. A study by (May J, 2000) found that Individuals describing loud noise on the job, which required the necessity of shouting to communicate with co-workers, or ringing/ buzzing following work exposures may well be experiencing excessively high levels of noise. Dobie, (1993) states that, the need to shout in order to converse suggests the possibility of a possible hazardous exposure, although hazard is negligible in the 80 -85 dB (A) range. This theory is backed up by (Porter 1993) who states, “A rule of thumb, however, is that if a person normally has to shout to communicate to workmates, he is at risk of developing noise induced hearing loss”.
A point to be considered is the possibility of instructors not playing music as loud as they might normally do because of the awareness of the study and consciousness that loud music may affect their hearing (Hawthorne effect).
A further limitation may have been the use of the Dosimeter itself. The design of the dosimeter meant that the microphone often came into contact with the instructor which resulted in high peak values. This was found to be the likely reasoning behind the extremely high peak values which may have also affected the daily exposure value.
The high levels of noise found by the study are not surprising due to the lack of training and awareness of Noise at Work Regulations (Noise Regs). The study found that no instructors had received training and only one instructor was aware of the Noise Regs.
The lack of training may be linked to the lack of understanding and under estimation of noise levels they were using in their classes. Nearly all instructors found that the music they were using was at an ‘about right’ level and not be harmful to hearing, despite a mean daily exposure of 80 dB (A). The use of language to estimate noise levels was used due to instructors not understanding decibels and its associated meaning. It was decided this would be a simpler means of estimating noise levels.
5.3 Study limitationsThe use of dosimetry gave the most life like measuring of noise exposure; however, the microphone was still over 10cm from the ear canal, the point in which noise is processed. The affect of the acoustics of the rooms and its reverberation will also not be taken into account by the dosimeter.
The design of the dosimeter prevented recording being taken from any closer than 10cm. This may have resulted in affecting the results. The design of the dosimeter also meant the microphone had to be clipped on the neck area of an instructor’s upper most garments. This led to the microphone rubbing against the neck and jaw of the instructor, resulting in an increased and unreliable peak action value.
The dimensions of arenas where measurement were taken varied from small studios to a large gymnasium. For this reason the reverberation attributes of room were not taken into consideration. The range of different rooms used may have an effect on noise levels reaching the dosimeter. However, the use of dosimetry provided the most realistic measurement possible.
A more accurate measurement would have been possible if the background noise levels had been recorded and taken into consideration when analysing results, however, this was not always possible due to the quick turn-around of classes which left no time for background noise levels to be recorded.
The cross sectional study was straightforward due to its convenience, which allowed correlations to be made from measurements and the questionnaire. Due to time constraints and funding, convenience sampling limited the study to the North Yorkshire and Leeds City area. This meant only a small population could be sampled, meaning it is difficult to regard as representative of the profession.
The questionnaire relied upon the instructor answering questions honestly. With this in mind, it is feasible that instructors experienced self awareness, recall bias and time constraints which lead to an inaccurate completion of questionnaire.
Chapter Six Conclusion Conclusion6.1This study was based on a small, cross sectional empirical method to address the exposure of fitness instructors to their noisy work environment. The study considered the frequency of classes and their duration, contrasting to prior studies mentioned earlier in this dissertation.
The study focused on the daily exposure of instructors, unlike the other studies, however, it only focused on the results gathered from one class. This limited results as further speculation would have meant assuming noise levels in other were classes were the same as the measured class, which would bring in the issue of bias.
Similarly, it is possible that the weekly exposure could have been calculated based on noise levels recorded, but this again would have required an assumption that all other classes were the taught at the same noise level, which is unlikely due to the varying locations instructors are likely to teach. This assumption would have led to an unrealistic under or over estimation of noise levels.
To accurately estimate weekly exposure levels would have meant attending more classes which was not possible in the timeframe of this study. It was also felt that this would have placed too much of a burden on instructors and lead to a lower number of fully participating participants
The questionnaire proved reliable due to its short length, however, it was restricted to by its small sample population and the use of convenience sampling which meant it was not possible to generalisation of results.
This study has provided an insight into the noise levels that instructors are using within the workplace and considered factors that may influence the levels that are used. Although this study is not representative of the industry sector as a whole, couple with other similar studies that have returned similar results, it provides further evidence that this is an industry that is not being address adequately by the Control of Noise at Work Regulations 2006.
It has not only addressed the workplace environment noise but has considered the whole exposure of the instructors and this information would be useful when attempting to develop and implement a hearing conservation programme. Although this study was not able to determine the relative risks and odds ratio for the different risk factors and their statistical significance, it did provide a valuable insight in the role of a fitness instructor and much information for dissemination which would assist in understanding the nature of the risks that instructors face. Again, this would not be representative of that sector; however, with other studies reporting similar high noise levels, it is further evidence that this is an area, which needs to be addressed. The study has also identified that there is a lack of training and perception of noise levels.
This study focused solely on the noise levels of amplified music and did not consider noise from equipment, people attending the class or acoustics of the room.
The potential for instructors to have experienced bias or self awareness whilst completing the questionnaire has been noted. The margin of error in recording noise measurements has also been considered however has not been clarified to use in conjunction with results.
6.2 Results summarySoderquist (2002) states that NIHL can cause a temporary threshold shift and lead to the decrease in sensitivity, and increase in threshold, which occurs when you are exposed to a long duration of sound that has a level greater than 80 dB. The results from this study found noise levels in fitness classes to range between 81 dB (A) and 95 dB (A), with a mean of 89 dB (A) and personal daily exposure based on one class of between 71 dB (A) and 85 dB (A) with a mean of 80 dB (A). However this result is likely to have been underestimated as mentioned earlier in this chapter.
The results showed that four (57%) of the instructors music levels were above the first action value in the Noise at Work Regs 2006 and two of those over the second action value of 82 dB(A). Despite the remaining results recording values below the first action value, it must be noted that they still achieved a Lep’d no lower than 77 dB (A). These instructors are running a risk of suffering from Noise Induced Hearing Loss, which is compounded by the frequency of classes they teach and lack of training and awareness of regulations.
Leisure centres were fitness classes take place are allowing breaches of legislation (Control at Noise Regulation 2006) to occur, which is proving detrimental to employees. None of the instructors involved in this study had received training of noise levels. A consequence of this is shown in the majority of instructors believing the noise levels used in their classes was ‘about right’ or ‘quiet’ despite being above the lower action values of the noise regs. Potentially further detrimental is that 71.5% of instructors have hobbies that involve loud music, which is likely to be louder than fitness classes due to thinking that their fitness class didn’t involve loud music.
Chapter Seven Recommendations Recommendation 7.1This study has demonstrated the issue of noise in fitness classes and the need for further research to enable further generalisation of the population. A more extensive population would provide evidence of causality. Performing measurements over a week basis for instructors would also provide more accurate and reliable daily exposure value.
Future research may also want to make further correlations using tests to measure symptoms of hearing loss. A further point to take into consideration is to consider acoustics of arenas, the reverberation characteristics of the room and other factors that may increase background noise levels.
The study limitation of instructors’ awareness of the study and possible lowering of volume is a difficult problem to address due to ethical reasons. The use of a sound level meter to perform measurements is less intrusive to the instructor, however, will provide less realistic results.
A concern highlighted by this study was the lack of training on noise related issues received by instructors. The use of loud music is integral to the instructing of fitness classes; however, it is not being addressed by management in leisure centres. This study has highlighted the need for training and developing of health surveillance in this sector. Torre and Howell (1999) found that aerobics instructors often used high levels of music to motivate the class; these levels of music, in combination with the instructor’s encouraging voice at a higher level, may contribute, over time, to recreational noise-induced hearing loss. Furthermore Clark and Calvert (1991) suggested that the use of music during fitness classes improves the performance of participants, and often noisy environment are necessary for the enjoyment of the activity. This is called the “social noise phenomenon”. For change in attitudes towards hearing protection and strategies to reduce volumes, first, the above attitude must be overcome.
An alternative measure to tackle problems identified in this study is to place more emphasis on the management of leisure centres. Methods may include a contract between management and instructors to not exceed preset volume levels or placing noise level limiting equipment on audio equipment. However, this may be difficult to monitor due the varying background noise levels found in different classes and its number of participants.
Management of leisure centres need to consider the risk of Noise Induced Hearing Loss of instructors within its workplace. Identification of typical noise levels will allow for policies and agreements to be put in place to protect its employees from a life changing medical condition. It should also be realised that the use of increasing sound levels to motivate participants during fitness classes may put regular gym-goers, as well as instructors, at an increased risk of NIHL.
Reference listAndersson, G., Baguley, D. M., McKenna, L., & McFerran, D. (2005). Tinnitus: A multidisciplinary approach. London:Whurr Publishers.
Andersson, G., Eriksson, J., Lundh, L. G., & Lytkkens, L. (2000). Tinnitus and cognitive interference: A Stroop paradigm study. 104 Biological Research for Nursing 13(1) Journal of Speech, Hearing and Language Research, 43, 1168-1173.
Carter, N.L., Murray, N.M., Khan, A., Waugh, R.L. (1984). A longitudinal study of recreational noise and young people’s hearing. Australian Journal of Audiology, 6, 45-53.
Cone, J and Hayes S (1985). Environmental Problems/Behavioral Solutions. London: Cambridge University Press. p89.
Daniel E. (2007).Noise and hearing loss: a review. Journal of School Health77 (5): 225-31
Davies AC, Fortnum HM, Coles RRA et al. Damage to hearing from leisure noise: a review of the literature. Nottingham: Medical Research Council Institute for Hearing Research, University of Nottingham, 1985
Diaz C., Pedrero A. (2006). Sound exposure during daily activities. Applied Acoustics 67: 271-283
Dobie, R A (1993). Medical-legal evaluation of hearing loss. 2nd ed. New York: Van Nostrand Reinhold. p163.
European Agency for Safety and Health at Work. (2005). Hearing loss in the EU-15 General prevalence. European Agency for Safety and Health at Work
Howley & Franks (2007) Fitness professionals handbook Human Kinetics; 5 edition p264
HSE (2005). Likely noise reduction. The Control of Noise at Work Regulations 2005: Guidance on Regulations. Likely noise reduction (278), p78
Jons CM. Occupational hearing loss and vibration induced disorders. Br Med J 1996; 313: 223-226
May, J. (200). Clinical features. Occupational Hearing Loss. 1 (3), p114.
Mirbod, S. M., Lanphere, C., Fujita, S., Komura, Y., Inaba, R., & Iwata, H. (1994). Noise in aerobic facilities. Industrial Health, 32, 49–55.
Moller, A.R.; Langguth, B.; DeRidder, D.; Kleinjung, T. (2010). Textbook of Tinnitus. New York: Springer. p302.
Palmer, et al. (2001). Occupational exposure to noise and hearing difficulties in Great Britain. HSE Research Report. 1 (Table 5 ), p12.
Peters R.J. (2003). The Role of Hearing Protectors in Leisure Noise. Noise and Health 5 (18): 47-55
Porter, MJ. (1993). Sensorineural Hearing Loss. Otorhinolaryngology, Head & Neck Surgery. 15 (11), p2864.
Soderquist, D (2002). Sensory processes. London: SAGE. p272.
WHO. (1997). PREVENTION OF NOISE-INDUCED HEARING LOSS. Available: http://www.who.int/pbd/deafness/en/noise.pdf. Last accessed 11th March 2011.
William, R (2007). Environmental and Occupational Medicine. 4th ed. Philadelphia: Lippincott Williams & Wilkins. p1927.
Yarenchuk KL, Kaczor JC. (1999). Noise levels in the health club setting. Ear Nose and Throat Journal 78: 54,57
