Isometric endurance of the back extensors in school-aged adolescents with and without low back pain.
OBJECTIVE
Studies on back extensor endurance in adolescents are scarce. This study sought to establish reference data and pattern of back extensor endurance in school-aged adolescents with and without low-back pain (LBP) from Nigeria.


METHODS
This study recruited 625 adolescents aged 11 to 19 years from eight randomly selected secondary schools. The modified Biering-Sørensen test of Static Muscular Endurance (BSME) was used to assess isometric endurance of the back extensors. Demographic and anthropometric data were collected. A modified LBP questionnaire was used to assess the presence of LBP. Descriptive and inferential analyses were used to analyze data. Significance was set at 0.05 alpha-level.


RESULTS
The mean isometric holding time (IHT) of all the participants was 132.9 $\pm$ 65.6. Males had significantly higher significant (p=0.026) IHT than females. Adolescents without LBP had a higher significant IHT (p=0.042) than those with reported history of previous LBP and those with present LBP (p=0.000) respectively. Using percentile values, poor endurance was defined as IHT that is < 90.0 s and < 67 s for males and females respectively; medium endurance was defined as IHT that ranged between 90 and 193 s and 67 and 170 s for males and females respectively while good endurance was defined as IHT that is > 193 s and > 170 s for males and females respectively. IHT was significantly related to each of body mass index, hip circumference and waist-to-hip ratio (p < 0.05).


CONCLUSIONS
Isometric back extensors endurance in Nigerian adolescents was comparable to the original Biering-Sørensen mean value. Majority of the participants had medium endurance performance with the back endurance pattern in the ratio 1:2:1. Male had higher isometric back extensors endurance than females. Decreased isometric back extensors endurance was associated with the presence of LBP in adolescents.
Johnson
Olubusola E
OE
Department of Medical Rehabilitation, Obafemi Awolowo University, Ile-Ife, Nigeria. obnik2001@yahoo.co.uk
Mbada
Chidozie E
CE
Akosile
Christopher O
CO
Agbeja
Oyinade A
OA
D000293:Adolescent; D001415:Back / Q000502:physiology*; D015992:Body Mass Index; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D017116:Low Back Pain / Q000503:physiopathology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D009549:Nigeria; D010807:Physical Endurance / Q000502:physiology*; D016684:Prone Position / Q000502:physiology; D012727:Sex Characteristics; D013997:Time Factors; D055815:Young Adult