3.5 Results and Discussion
3.5.4 Comparative assessment of the present study with other (inter)national
contrary, Harris (1969) study on the U.S student population was unable to acquire any single general characteristic (dominant PC) for joint flexibility.
3.5.4 Comparative assessment of the present study with other (inter)national databases of
When comparing present study with the anthropometric data of 70 motorcyclists from Pune (city of India) extracted from Amrutkar and Rajhans (2011), we found that the percentage differences were ranging from -11% to 11%. In particular, the knee height, buttock–popliteal length, lower-leg length, and shoulder–elbow length exhibited differences of more than 6%
between the aforementioned two databases. Similar levels of percentage differences were found when the database of the present study was compared with India’s general population (Chakrabarti, 1997). Moreover, it shows that the anthropometric dimensions of the Indian motorcyclist population (considering six zones) were higher than the dimensions of both generals (Chakrabarti, 1997) and specific city (Pune) (Amrutkar and Rajhans, 2011) population of India. Perhaps this could be the reason of comparing different type of sampling studies i.e.
biased-sampling/ specific-location of the country and unbiased-sampling/ considering six zones of the country.
The Indian (present study) and British motorcyclist (Robertson and Minter, 1996) comparisons showed a general trend of larger dimensions in the U.K population. The dimensional differences varied from -20% to 2%. The percentage difference in stature and weight was very high at -20% and -5%, respectively. Perhaps the reason for this high difference could be the geographical diversity among the motorcyclists. Except for knee height, these results showed that the anthropometric dimensions of Indian motorcyclists were smaller than the U.K
The dimensional differences between Nigerian (Imaekhai Lawrence, 2013) and Indian motorcyclists ranged from -9% to 8%. Except for acromion grip length, the percentage differences of the anthropometric dimensions of the Indian motorcyclist were higher than the Nigerian. The dimensions viz. acromion grip length, buttock-popliteal length, and lower leg length explicitly found larger (more than 7%) in Indian motorcyclists. Unlike the comparison of Indians with British anthropometry, the results point out that most of the anthropometric characteristics of Nigerian motorcycle riders were smaller than Indians.
Overall, the results showed that there was profound difference in most of the anthropometric dimensions between the non-Indian and Indian motorcyclist populations. Moreover, region- specific anthropometry studies would not be a reliable representation and accurate estimate of Indian motorcyclists. Although higher dimensional differences were evident while comparing general Indian population data, most of the Indian driver’s anthropometry were more or less similar to Indian motorcyclists (present study).
Note: M is mean values (All unit are in cm) of anthropometric dimensions; %D = Percentage differences; Italic style numbers are 50th percentiles values of anthropometric dimensions; NA - Not mentioned
Table 3. 9: Comparative analysis - Anthropometric dimensions
Present study
National database International
Chakrabarti, 1997
Kulkarni et al., 2011
Shamasundara and Ogale,
1999
Amrutkar and Rajhans, 2011
Robertson and Minter,
1996
Imaekhai Lawrence
2013 Gender and origin/
type of population
Male motorcyclist
India
General male Indian
Indian drivers male
Indian drivers male
Motorcyclist of (Pune) city,
India
Male motorcyclist
UK
Male motorcyclist
Nigeria
Sample size (only male) 120 710 N/M 1091 N/M 108 160
Anthropometric
Dimension M %D M %D M %D M %D M %D M %D
W -Weight( in kg) 68 57 16 64 6 NA NA 82 -20 N/A
S - Stature 169 165 2 167 1 167 1 NA 177 -5 166 2
CH - Crotch height ) 78 77 2 73 6 NA 76 2 82 -4 NA
BE- Buttock extension 84 84 0 NA NA 83 1 NA NA
EHS- Elbow height, Sitting 22 22 2 NA NA 21 4 NA NA
KH -Knee height 55 52 6 NA 49 -11 51 7 54 2 52 6
LLL- Lower leg length 45 43 5 NA NA 42 7 NA 42 7
SEL -Shoulder-elbow length 35 32 10 NA 35 -1 31 11 NA NA
EHL -Elbow-hand length 47 NA NA 46 -2 NA NA NA
BKL- Buttock-knee length 59 56 6 NA NA NA 63 -7 55 7
PL -Buttock-Popliteal length 49 46 7 NA NA 45 8 NA 45 8
AL -Acromion grip length 63 NA NA NA NA 66 -5 69 -9
BFL -Ball of foot length 18 NA NA NA 20 -11 NA NA
HL-Hand length 18 18 -1 NA 19 -3 18 1 NA NA
FB-Foot-breadth 10 NA NA 10 -1 9 7 NA NA
EEB- Elbow-Elbow breadth 43 41 4 NA NA 40 7 NA NA
HBS-Hip breadth, sitting 34 33 2 NA 35 -2 NA 38 -11 NA
Table 3. 10: Comparative analysis - ROM measurements Gender and origin/type of
population Sample size
Present study - Male Indian Motorcyclist
120
Chakrabarti, 1997 - General Male Indian
961
ROM measurements M M %D
NF -Neck Flexion 37 45 -21
NE -Neck Extension 40 30 24
LF -Lumbar Flexion 104 90 14
LE -Lumbar Extension 21 10 53
WF- Wrist Flexion 75 80 -7
WE -Wrist Extension 69 65 5
EE -Elbow Extension 2 NA
EF -Elbow Flexion 140 145 -3
SF -Shoulder Flexion 164 180 -10
SE- Shoulder Extension 44 45 -3
HE -Hip Extension 17 20 -17
HF- Hip Flexion 107 110 -3
KF- Knee Flexion 128 135 -6
KE- Knee Extension 2 NA
AP- Ankle Plantarflexion 36 45 -26
AD- Ankle Doris flexion 19 40 -33
Note: M - Mean values (All unit are in °) of ROM measurements; %D = Percentage differences;
NA – Not mentioned
Since, along with anthropometry, ROM measurements are essential for the effective design of motorcycles, the ROM data from the present study were compared with general Indian population data (Chakrabarti, 1997). Table 3.10 shows the variation in mean ROM difference between Indian motorcyclists with the general population (Chakrabarti, 1997). The average angular difference was -29% ranged from -33% to 53%. The angular difference of lower limbs among Indian motorcyclists was smaller than the general population, whereas it was higher in the case of upper limbs. Hence, the ROM of the Indian motorcyclist was notably different from the general population.
To date, to the best of our literature search, the motorcyclist ROM measurements and its comparison with the general population have never previously been studied. The present study is first of its kind to undertake this approach. Collectively, the empirical evidence from the quantitative analyses can lead to gain attention to the researchers and ergonomists for conducting large-scale surveys to develop anthropometry and ROM database required for the ergonomics design of Indian motorcycles.
