Subjectively and objectively measured physical activity and its relationships with overweight and obesity in adolescent boys
Date
2016-09-07
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Abstract
Kehaline aktiivsus väheneb eluaaja jooksul ning samaaegselt suureneb ka istuva eluviisi aeg. Uuringutes on leitud, et subjektiivsed kehalise aktiivsuse mõõtmise meetodid on küll seotud objektiivselt mõõdetud kehalise aktiivsuse meetodidega, kuid see seos on sageli nõrk, ning pigem alahindavad kehalist aktiivsust. Käesoleva doktoritöö eesmärgiks oli uurida subjektiivselt ja objektiivselt mõõdetud kehalise aktiivsuse seoseid normaal- ja ülekaalulistel puberteedieas poistel.
Vastavalt uurimistöö eesmärgile püstitati järgmised konkreetsed ülesanded:
1. võrrelda omavahel puberteediealiste poistel subjektiivseid ja objektiivseid kehalise aktiivsuse parameetreid;
2. võrrelda normaal- ja ülekaalulistel puberteediealistel poiste ja lapsevanema subjektiivseid kehalise aktiivsuse hinnanguid akseleromeetriga määratud kehalise aktiivsuse tasemetega;
3. jälgida normaal- ja ülekaaluliste puberteediealiste poiste objektiivselt ja subjektiivselt mõõdetud kehalise aktiivsuse muutust kahe aasta jooksul;
4. uurida kahe aasta jooksul puberteediealistel poistel kehalise aktiivsuse seost ülekaalulisusega.
Antud uuringus osalesid 11-14-aastased poisslapsed. Vaatlusalused jaotati kehamassi indeksi järgi normaal- ja ülekaalulisteks ning neid uuriti kahe aastase jooksul kolmel korral. Igal aastal toimusid mõõtmised samal aastaajal ning uurimispäeval määrati vaatlusalustel keha koostis ning samuti täitsid uuritavad kehalise aktiivsuse küsimustikud. Seejärel kandsid nad akseleromeetrit seisme päeva jooksul. Lisaks täitis lapsevanem küsimustiku oma lapse kehalise aktiivsuse kohta.
Käesoleva doktoritöö põhjal tehti järgmised järeldused:
1. Vaatlusalused alahindasid subjektiivselt mõõduka kuni tugeva kehalise aktiivsuse (MTKA) taset võrreldes akseleromeetriga määratud kehalise aktiivusega. MTKA alahindamine leiti aktiivsematel poistel, kelle igapäevane MTKA hulk oli vähemalt 60 minutit päevas, seevastu vähem aktiivsetel poistel usutavat erinevust ei leitud .
2. Subjektiivselt määrasid oma kehalise aktiivsuse taset oluliselt täpsemini ülekaalulised vaatlusalused võrreldes normaalkaalulistega. Lapsevanema subjektiivne hinnang ennustas oluliselt paremini lapse inaktiivsuse taset, võrreldes lapse enda subjektiivse hinnanguga, seevastu mingit usutavat erinevust lapse ja lapsevanemate hinnangutes ei leitud subjektiivse ja objektiivse MTKA vahel.
3. Subjektiivselt ja objektiivselt mõõdetud kehalise aktiivsuse muutus normaal- ja ülekaalulistel puberteediealistel poistel oli kahe aasta jooksul üsna stabiilne.
Tugeva kehalise aktiivsuse tase omab kõige tugevamat seost ülekaalulisuse ja rasvumisega puberteedieas poistel ning päevane liikumine peab sisaldama vähemasti 15 minutit tugevat kehalist aktiivsust 60 minuti MTKA hulgas, et vältida ülekaalu või rasvumist puberteedieas.
Physical activity decreases during the life-span and at the same time there is continuous increase in sedentary behaviour. Different studies have found that subjective ratings of physical activity are related to objective measures, but the association is weak, in general and usually underestimate physical activity. The general aim of the present thesis was to investigate the association of subjectively and objectively measured physical activity and physical activity contribution to weight status in pubertal boys. According to the general aim, the specific aims of present thesis were to: 1. compare different self-report physical activity questionnaires with accelerometer measured physical activity data in pubertal boys; 2. compare the subjective physical activity ratings of children and parent with accelerometer based physical activity in normal, overweight andobese boys; 3. examine the tracking of physical activity between accelerometer with children and parental subjective ratings in normal weight and overweight pubertal boys over two-year period; 4. examine how the fulfillment of different physical activity recommendations, different physical activity cut-offs and sedentary time associate with the risk of being overweight or obese during the puberty over the two-year period in pubertal boys. Partisipants of the study were 11-14-years old pubertal boys. On the basis of body mass index (BMI), the boys were grouped as normal weight, overweight and obese. During a research day, all participants completed self-report PA questionnaires and wore an accelerometer for seven consecutive days. Parents used the same questionnaires for evaluating their child’s physical activity. Based on the results the following conclusions were made: 1. The boys under-report their moderate-to-vigorous physical activity (MVPA) compared to subjective ratings. Underreporting was more marked in active boys, whose daily MVPA was at least 60 minutes, and was not significant in less active boys. 2. Overweight boys assess subjectively their physical activity better compared to normal weight boys. Parent subjective ratings predicted sedentary time better than boys’ self-report but no difference was found for MVPA. 3. The tracking correlations of physical activity between objective assessment and subjective ratings of physical activity were similar across the two-year period in pubertal boys of different weight status. 4. Vigorous physical activity is important for predicting overweight and obesity in boys during puberty and at least 15 minutes of vigorous activity should be used within 60 min MVPA every day to reduce the risk of developing overweight and obesity in later puberty.
Physical activity decreases during the life-span and at the same time there is continuous increase in sedentary behaviour. Different studies have found that subjective ratings of physical activity are related to objective measures, but the association is weak, in general and usually underestimate physical activity. The general aim of the present thesis was to investigate the association of subjectively and objectively measured physical activity and physical activity contribution to weight status in pubertal boys. According to the general aim, the specific aims of present thesis were to: 1. compare different self-report physical activity questionnaires with accelerometer measured physical activity data in pubertal boys; 2. compare the subjective physical activity ratings of children and parent with accelerometer based physical activity in normal, overweight andobese boys; 3. examine the tracking of physical activity between accelerometer with children and parental subjective ratings in normal weight and overweight pubertal boys over two-year period; 4. examine how the fulfillment of different physical activity recommendations, different physical activity cut-offs and sedentary time associate with the risk of being overweight or obese during the puberty over the two-year period in pubertal boys. Partisipants of the study were 11-14-years old pubertal boys. On the basis of body mass index (BMI), the boys were grouped as normal weight, overweight and obese. During a research day, all participants completed self-report PA questionnaires and wore an accelerometer for seven consecutive days. Parents used the same questionnaires for evaluating their child’s physical activity. Based on the results the following conclusions were made: 1. The boys under-report their moderate-to-vigorous physical activity (MVPA) compared to subjective ratings. Underreporting was more marked in active boys, whose daily MVPA was at least 60 minutes, and was not significant in less active boys. 2. Overweight boys assess subjectively their physical activity better compared to normal weight boys. Parent subjective ratings predicted sedentary time better than boys’ self-report but no difference was found for MVPA. 3. The tracking correlations of physical activity between objective assessment and subjective ratings of physical activity were similar across the two-year period in pubertal boys of different weight status. 4. Vigorous physical activity is important for predicting overweight and obesity in boys during puberty and at least 15 minutes of vigorous activity should be used within 60 min MVPA every day to reduce the risk of developing overweight and obesity in later puberty.
Description
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Keywords
teismelised, poisid, füüsiline aktiivsus, kehakaal, ülekaalulisus, teenagers, boys, physical activity, body weight, overweight