Fysisk aktivitet för barn och ungdomar

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1 Fysisk aktivitet för barn och ungdomar Örjan Ekblom, docent Åstrandlaboratoriet, GIH Exponering Begreppet fysisk aktivitet Fysisk aktivitet - Intensitet - Typ - Frekvens Stillasittande - Breaks Prestation - VO2 - Styrka - Balans Mekanism Hjärta/kärl Kolesteroler Insulin LPL Muskel Myokiner Transportörer DNA Telomerer CNS BDNF Riskfaktorer Plaque Hypertoni Dålig sockerkontroll Obesitas Hormonella rubbningar Blodfettrubbningar Utfall CVD NIDDM Kognitiva förmågor Depression Demens Cancer Trender hos barn och unga Hos 15 åringar minskade tiden i MVPA från 52 till 40 minuter per dag hos flickor och från 56 till 46 minuter per dag hos pojkar mellan 1998 till 2004 Ca 20 minuter ökning i tid i stillasittande under samma tid. Ortega et al PLoS One 2013) Ung Livsstil 2009 (Blomdahl och medarbetare) Pojkar Mellan 50 Flickor Mellan 40 Pojkar Hög 30 Flickor hög 20 Pojkar Gy 10 Flickor Gy Räcker medlemskap? Hos nioåringar ger en fotbollsmatch ca 25% av behovet MVPA (= träning )! (Schaeck et al 2011) 1

2 Metabola konsekvenser Indirekta tecken på trender i aktivitet Andel överviktiga och feta Ekblom et al. Trends in aerobic fitness in Swedish adolescents Kondition kan tränas hos barn. Kontinuerlig träning och intervallträning, exempelvis löpning, simning, cykling. Intensitet: I medeltal 85 procent av maximal puls under passet. Duration: minuter per gång. Frekvens: 3 4 dagar i veckan. Träningsperiodens längd: Minst 12 veckor Janssen I, Leblanc AG. IJBNPA, Armstrong N, Medicine and sport science 2011 Table 1 Number of subjects, anthropometric characteristics and ages for subjects in the three samples Height, cm Body mass, kg BMI, kg m 2 Age, year Sample N (girls boys) Mean (SD) Mean (SD) Mean (SD) Mean (SD) (125 96) (8.8) 61.5 (10.2) 21.0 (2.3) 16.3 (0.9) ( ) (8.4) 63.1 (10.3) 21.7 (3.0) 15.8 (0.3) ( ) (8.2) 64.5 (11.9) 21.7 (3.3) 15.8 (0.3) Aerobic capacity (1/min), 95% CI Girls Boys , respectively. In girls, corresponding values from 1987, 2001 and 2007 were 45.9 ( ) ml min, 40.4 ( ) ml min and 36.6 ( ) ml min kg, respectively. Significant gender (p < 0.001) and sample (p < 0.001) differences were found, but no gender-by- sample interaction (p = 0.09). After adjusting for the clustering effect from the sampling procedure, both the gender difference (p < 0.001) and the difference between samples were still significant (p < 0.001). Post hoc analyses revealed that compared to 1987, values for estimated relative and absolute maximal aerobic capacities were lower in 2001 and 2007, and values in 2007 were lower compared to 2001, in both boys and girls, except for absolute capacity between 1987 and 2001 in girls. The 10th, 25th, median 75th and 90th percentiles for absolute and relative aerobic capacity in girls and boys from each sample are shown in Table 2a and b. DISCUSSION The main result from this study is that there is a difference between the three samples in both absolute and relative estimatedetaerobic al. capacities between girls and boys of 16 years Ekblom of age during the last 20 years. The differences between samples were rather general and not dependent upon an Table 1 Number of subjects, anthropometric characteristics and ages for sub- increased range or change in either extreme of the distribution. The post hoc analyses also revealed differences BMI, kg m 2 Age, year between all groups but one, indicating amean steady (SD) and Mean (SD) evenly distributed change over time. However, the trends seem (125 96) (8.8) 61.5 (10.2) 21.0 (2.3) 16.3 (0.9) somewhat more decreased between 2001 and 2007, but ( ) (8.4) 63.1 (10.3) 21.7 (3.0) 15.8 (0.3) 2007 boys and 264 (105 girls 160) do not differ (8.2) in64.5 change (11.9) over 21.7 time (3.3) (evident 15.8 (0.3) by the absence of gender-by-sample interactions). Secular trends in aerobic capacity in Swedish adults between and 2001 have been reported previously (24). The gap in aerobic fitness between Swedish men and 3.2 Girls women has been reduced over the period betweenboys 1990 and 2000, partly attributable to a more pronounced decline in 3.0 physical fitness levels among men, compared to women. Trends in aerobic fitness among Swedish adolescents and 2.8 adults thus seem to differ. During the period between the late 1980s and about , prevalence of overweight and obesity has increased steeply. 2.4 Since then, the increase seems to have stopped (21,22). One possible explanation may be that, in the late 1980s, 2.2 physical activity decreased, but energy intake remained on an unchanged level, leading to decreased aerobic 2.0 fitness and increased rates of overweight and obesity. The0.0 discrepancies between secular trend in overweight or obesity and aerobic fitness between 2001 and 2007 may Year come from a continued reduction in physical activity, but Figure with 1a Mean matched and 95% energy CI forintake. absolute aerobic capacity adjusted for age, in girlsthe and boys reason in samples for a1987, decline 2001in andaerobic Significant fitnessgender in adolescents and sample is differences not known. were found, Changes which remained lifestyle after adjusting are naturally for the clustering central. Ekblom,et al Acta Paediatrica 2011 effect Unfortunately, (both p < 0.001). objective data on trends in type, frequency or intensity of the physical activity performed are lacking. The50increase in prevalence of overweight and obesity may to some extent explain the decline in relative fitness, Girls but not 48 Boys in absolute values. It seems logical to conclude that physical Indirekta tecken Year jects in the three samples på trender i aktivitet Height, cm Body mass, kg Sample N (girls boys) Mean (SD) Mean (SD) Est. VO Figure 1 Mean and 95% CI for absolute aerobic capacity adjusted for age, in girls and boys in samples 1987, 2001 and Significant gender and sample differences were found, which remained after adjusting for the clustering effect (both p < 0.001). 50 Girls 48 Boys Relative aerobic fitness (ml/min/kg), 95% CI Year Figure 2 Mean and 95% CI for relative aerobic fitness, adjusted for age in girls and boys in samples 1987, 2001 and Significant gender and sample differences were found, which remained significant after adjusting for the clustering effect (both p < 0.001). The relative aerobic capacity in boys decreased from 46.5 ( ) ml min kg in 1987 to 44.1 ( ) ml min and 38.0 ( ) ml min kg in 2001 and ª2011 The Author(s)/Acta Pædiatrica ª2011 Foundation Acta Pædiatrica , pp Year Figure 2 Mean and 95% CI for relative aerobic fitness, adjusted for age in girls and boys in samples 1987, 2001 and Significant gender and sample differences were found, which remained significant after adjusting for the clustering effect (both p < 0.001). The relative aerobic capacity in boys decreased from 46.5 ( ) ml min kg in 1987 to 44.1 ( ) ml min and 38.0 ( ) ml min kg in 2001 and Aerobic capacity (1/min), 95% CI Relative aerobic fitness (ml/min/kg), 95% CI Trends in aerobic fitness in 2007, respectively. In girls, corresponding 2001 and 2007 were 45.9 ( ) ml 41.6) ml min and 36.6 ( ) ml tively. Significant gender (p < (p < 0.001) differences were found, but no ple interaction (p = 0.09). After adjusting effect from the sampling procedure, both ence (p < 0.001) and the difference betw still significant (p < 0.001). Post hoc analyses revealed that compar for estimated relative and absolute maxim ties were lower in 2001 and 2007, and va lower compared to 2001, in both boys an absolute capacity between 1987 and 2001 The 10th, 25th, median 75th and 90 absolute and relative aerobic capacity in g each sample are shown in Table 2a and b. DISCUSSION The main result from this study is that th between the three samples in both absolut mated aerobic capacities between girls an of age during the last 20 years. The dif samples were rather general and not de increased range or change in either extrem tion. The post hoc analyses also rev between all groups but one, indicating a distributed change over time. However, somewhat more decreased between 200 boys and girls do not differ in change ove the absence of gender-by-sample interactio Secular trends in aerobic capacity in between 1990 and 2001 have been reporte The gap in aerobic fitness between S women has been reduced over the period b 2000, partly attributable to a more prono physical fitness levels among men, com Trends in aerobic fitness among Swedish adults thus seem to differ. During the period between the late 2000, prevalence of overweight and obes steeply. Since then, the increase seems (21,22). One possible explanation may b 1980s, physical activity decreased, bu remained on an unchanged level, leading t bic fitness and increased rates of overwe The discrepancies between secular trend obesity and aerobic fitness between 200 come from a continued reduction in phy with a matched energy intake. The reason for a decline in aerobic fitn is not known. Changes in lifestyle are Unfortunately, objective data on trends i or intensity of the physical activity perfo The increase in prevalence 2 of overweight to some extent explain the decline in relat in absolute values. It seems logical to conc ª2011 The Author(s)/Acta Pædiatrica ª2011 Foundation Acta Pædiatrica , pp

3 Kondition och metabola konsekvenser Rizzo et al J Pediatr 2007 HUR KAN DESSA SKILLNADER UPPKOMMA? Styrketräning Det finns i tvärsnittsstudier ett positivt samband mellan muskelstärkande träning och muskelstyrka hos både barn och ungdomar. 2 3 gånger i vecka i minst 8 veckor Tyngden på vikterna/motståndet hade ingen säkerställd betydelse. Behringer M. Pediatrics 2010 Muskelmassa och typ är kopplat till skeletthälsa, sockertålighet och hjärthälsa. Styrka är viktigt för att klara rörelser och minska skaderisk Skeletthälsa Friska barn som i experimentella studier utför regelbunden och viktbelastande aktivitet (exempelvis hopp, styrketräning, acceleration och inbromsning) har uppvisat positiva effekter på benmineraltäthet. Aktiviteten utfördes minst 2 3 gånger i veckan och durationen var 3 60 minuter. Träningsperiodens längd var 2 månader till 2 år. Janssen IJBNPA, 2008 Funktion i ämnesomsättningen Insulinkänslighet Styrketräning och konditionsträning påverkar gynnsamt Fedawa FA Pediatrics 2014, Berman LJ, Diabetes 2012,Kim Y, Int J Edocrin 2013 Blodtryck Konditionsträning tycks ge säkrast blodtryckssänkande effekt, men träningens utformning behöver undersökas närmare. Blodfetter Gynnsamma effekter av konditionsträning i kombination med kostrestriktioner på HDL och LDL, större än de som erhölls av enbart kostrestriktioner. Ho M, et al JAMA,

4 Study (year) Norris et al., [35] 1992 Melnyk et al., [33] 2009 Bonhauser et al., [36] 2005 Mendelson et al., [34] 2010 Hilyer et al., [31] 1982 Petty et al., [32] 2009 Annesi, [38] 2005 MacMahon and Gross, [37] 1988 Daley et al., [30] 2006 Subgroups within study Comparison Outcome Hedges g Standard error Statistics for each study Variance Lower limit Upper limit Z-value Combined Control Depression Combined Combined Depression Experimental Control Depression Intervention Control Depression Combined Combined Combined Combined Combined Depression Treatment Control Depression Combined Combined Depression p-value Hedges g and 95% CI Mental hälsa hur barn mår Studier på samband mellan mental hälsa/ohälsa hos barn och ungdomar och fysisk aktivitet är ännu förhållandevis få. I de studier som redovisats finner man positiva effekter av fysisk aktivitet på självkänsla och självuppfattning. Brown HE Sports Med 2013, Biddle, S, Br J Sport Med 2011, Larun L Cochrane Rev 2006 Sammanslagning av studier, meta-analys Combined Combined Depression Favours A Favours B Brown Fig. 2 Meta-analysis et al of depression Sport scores Med, in included 2013 Bättre Sämre studies. Forest plot of the mean overall standard mean deviation (95% confidence interval [CI]) and the standard mean deviation and associated 95% confidence interval and the associated standard estimations and variance for each study included in the analysis. The individual study effect sizes are represented by the centre of the square symbol associated with the study, a study s contribution toward the overall mean effect size (or weight) is represented by the symbol size and the precision of the study is represented by the length of the line associated with each symbol. A negative effect size denotes a programme that favoured the intervention group (e.g. a significantly greater decrease in screen time in the intervention group compared with the treatment group). Generally accepted criteria for effect-size magnitude are 0.2 \ small, 0.5 \ medium and 0.8 \ large 202 H. E. Brown et al. Fysisk aktivitet påverkar hjärnan Interventioner hos barn 120 fp Ca 66 år Promenader min Erickson et al PNAS 2011 Kamijo at al

5 Skolprestation eller kognition I tvärsnittsstudier liksom i experimentella studier har man funnit tydliga positiva samband mellan kondition och skolprestation, men mer sällan direkta, tydliga samband mellan grad av total fysisk aktivitet och skolprestation. Begränsat vetenskapligt underlag. Castelli DM, Journal of sport & exercise psychology Fedewa AL Research quarterly for exercise and sport Hillman CHDevelopmental psychology Hillman CH, Neuroscience Kamijo K. Developmental science Icke-linjärt samband kondition-kognition APPLIED SCIENCES FIGURE 1 Predicted achievement scores and trend lines for mathematics and spelling. In this study, PA was not significantly correlated with AA, either linearly or nonlinearly. There could be several reasons for this null finding. Hansen First, et PAal may MSSE not have 2014 a direct relation with AA. However, given the obvious role that moderateto-vigorous PA over time plays in improving or maintaining aerobic fitness, it seems more likely that this null finding is attributable to other factors. It could be that the unit of measure for PA in this study aggregate of 3 4 d of accelerometer data with valid data across four consecutive days may not have adequately represented the full scope of these children s typical activity levels. Valid PA data were also missing for a substantial proportion of children in this study (41.5%), and thus, this smaller subsample may not have adequately represented the relation of PA and AA for the entire sample. The present findings, however, point to the need for longitudinal designs that assess PA over longer periods or on multiple occasions to unmask any potential relation between PA and AA. REFERENCES 1. Ahamed Y, Macdonald H, Reed K, Naylor PJ, Liu-Ambrose T, McKay H. School-based physical activity does not compromise CONCLUSIONS This study has particular strengths and should be noted. Although the cross-sectio any evaluation of how/if PA and aerobic fit to AA over time, the findings indicated tha in this study were below the recommended levels. Barring hereditary and maturationa dren s fitness levels, most children should be ing recommended levels of PA and aerobic fit present findings suggest that increases in th benefit their AA. (Increasing PA is argued increasing fitness.) The use of salient covari ses, including gender, race, ethnicity, parenta household income, and BMI, strengthened ruling out their potential influence on the re aerobic fitness with AA. We suggest thatres mum, measure and evaluate the influence of t future studies in which AA is included. It sho that this study s sample was homogeneous (predominantly White) and there was a relati tion of high-income families (21%), which ability. Lastly, there is limited validity evidenc 20-m PACER in 7- to 8-yr-old children and confounding by motivation to perform or o due to the age of the sample is possible. Overall, the present study contributes to erature linking aerobic fitness and PA wi search implies that providing more opportun and improve fitness could improve AA, a and schools are uniquely situated to provid nities. With recent financial constraints on gets and increased pressures on schools to achievement standards, educators may be tem their focus on academics, perhaps to the det portunities for children in school. The findin along with existing research, suggest that th ultimately be detrimental to children s AA. research is needed to better understand the lo of increasing aerobic fitness and PA on childr present findings suggest that a more proac increasing fitness is warranted. We wish to express our appreciation to the s pated in this study. This study was supported by the National I (R01-DK85317). This trial was registered at the US of Health Clinical Trials, NCT The authors declare that they have no comp form of payment was given to anyone to produce The results of the present study do not constitu the American College of Sports Medicine. children s academic performance. Med Sci S 39(2): Official Journal of the American College of Sports Medicine Copyright 2014 by the American College of Sports Medicine. Unauthorized reproduction of this article is proh Skolprestation eller kognition Effekter av motorikträning och muskelstyrka är inte tillräckligt undersökta för att slutsatser ska kunna dras. De genomförda studierna har generellt metodologiska brister. Stroth S. Brain research 2009, Themanson JR Neuroscience 2006., Martin A Cochrane Rev Motorisk utveckling Svag koppling till kognition, inlärning, betyg. Akut koppling till aktivitet, övervikt, hälsa Upplevd Fysisk självkänsla, generell eller specifik Verklig Object control Balance Physical literacy Framtida aktivitet 5

6 Stillasittande Vid mätning med objektiva metoder har man inte kunnat finna ett samband mellan TV-tittande och tid i stillasittande hos barn och ungdomar. TV-tittande har däremot till exempel visats vara förenat med ohälsosamma matvanor såsom läskintag och småätande. Samband mellan ohälsa och objektivt uppmätt total inaktivitet (med accelerometer) har inte kunnat bevisas i den här åldersgruppen Ekelund et al Övervikt följer inte med sittande, men med aktivitet Ekelund et al JAMA 2015 of Behavioral Nutrition and Physical Activity 2014, 11:55 Page 7 of 10 1/1/ Endotelfunktion ett test Lowest third N=158 Middle third N=153 Highest third N=157 erence between groups analysed by GLM bolic risk score in thirds of total iometabolic risk score in lowest in/day) and highest (> 127 min/ ty adjusted for age and gender. els of total PA, particularly gher levels of SB, especially and resting, were associated etabolic risk. The combination and higher levels of EMT was ometabolic risk. udies on the associations of PA metabolic risk and overweight 0]. However, few studies have ether PA and SB are related to and body adiposity independent r individual cardiometabolic risk e European Youth Heart Study 0.75 Cardiometabolic risk score Low EMT High PA N= among children and adolescents, PA was not associated with body adiposity, but it was inversely related to overall cardiometabolic risk independent of watching TV and body adiposity [27]. However, watching TV was directly related to body adiposity and the direct association of watching TV with overall cardiometabolic risk was partly accounted for body adiposity and the frequency of meals. In contrast to the results of the European Youth Heart Study [27], our findings suggest that the inverse association of PA with overall cardiometabolic risk is largely explained by body adiposity. Consistent with the results of the European Youth Heart Study, however, the direct relationship of SB with overall cardiometabolic risk was partly accounted for body adiposity and the number of meals. We also observed that the direct association of watching TV with body adiposity was partly explained by total PA. These findings together suggest that some unhealthy eating behaviours accumulate 0.08 P=0.001 for difference between groups analysed by GLM Low EMT Low PA N=109 High EMT High PA N=110 High EMT Low PA N=126 Figure 3 Combined association physical activity and electronic media time with cardiometabolic risk score. Combined association of total physical activity (categorised at median of 107 min/day) and electronic media time (categorised at median of 96 min/day) with cardiometabolic risk score adjusted for age and gender. 6

7 Figure 1. Superficial femoral artery flow mediated dilation (FMD, %) before (Pre) and after (Post) the SIT and EX condition. Values are mean and standard deviations. The P values denote significance for the post-hoc pairwise comparison, Pre vs. Post EX and SIT. Figure 1. Superficial femoral artery flow mediated dilation (FMD, %) before (Pre) and after Endotelfunktion hos ungdomar (Post) the SIT and EX condition. Values are mean and standard deviations. The P values Effekt av tre timmars sittande (9 år gamla) denote significance for the post-hoc pairwise comparison, Pre vs. Post EX and SIT. McManus et al Exp Phys 2015 Corder et al. International Journal of Behavioral Nutrition and Physical Activity (2015) 12:106 Page 5 of 8 Table 2 Adjusted associations between academic achievement and physical activity/sedentary variables from multiple multilevel linear regression models Total points a Β (95 % CI) P value In separate models Sedentary time (hr/day) 6 9 (1 5, 12 4) MVPA (min/day) 1 8 ( 7 5, 3 8) Screen time (hr/day) 9 3 ( 14 3, 4 3) This article is protected by copyright. All rights reserved. 28 <0 001 Non-screen sedentary (hr/day) 23 1 (14 6, 31 6) Mutually adjusted Sedentary time (hr/day) 6 2 (0 6, 11 9) MVPA (min/day) 1 0 ( 5 7, 5 8) Screen time (hr/day) 9 1 ( 14 5, 3 7) Non-screen sedentary (hr/day) 24 7 (17 3, 32 0) <0 001 Quadratic functions Non-screen sedentary quadratic (hr/day)^2 8 3 ( 12 3, 4 3) <0 001 Non-screen sedentary (hr/day) 67 6 (44 8, 90 3) <0 001 All models clustered for school and adjusted for MFQ, BMI z-score, deprivation, season of physical activity measurement, and sex a Calculated to include GCSE and GNVQ results e.g., for GCSEs A* = 58, A = 52 G = 16, and similar for GNVQ grades Sedentary hr/day spent <1.5 METS MVPA mean mins/day spent in moderate and vigorous physical activity above 4 METS Screen time sedentary includes self-reported time spent in TV/DVD, Internet and Computer games Non Screen time sedentary includes self-reported time spent in homework and reading Quadratic functions are only shown if significant more GCSE points (equivalent to one whole GCSE (e.g., Contrary to our hypothesis, but similar to some recent Grade F=22 points)). These associations are independent findings [18], there was no association between academic suggesting that irrespective of the amount of reading and performance and MVPA. Our findings are contrary to a homework, screen time is still detrimental to GCSE performance, to the extent of 9 points or half a GCSE (at between MVPA at 11y and GCSE results (at 16y) in Eng- recent British study which concluded a positive association Grade G). lish for boys and Science for girls [19]. These associations Stillasittande och skolprestation Stillasittande This article is protected by copyright. All rights reserved. 28 Det finns otillräcklig evidens rörande stillasittande och dess effekter på hälsan under barn- och ungdomsåren. Ofta har skärmtid likställs med stillasittande tid. Studier tyder på ett samband mellan över två timmars TV- tittande/dag och flera mått på ohälsa Tremblay et al 2011, LeBlanc et al 2012 Fig. 1 Results are from two level linear regression models adjusted for MFQ, BMI z-score, deprivation, season of physical activity measurement and sex. Results are shown for objectively measured sedentary time and moderate and vigorous physical activity (MVPA), and self-reported separate and composite screen time (TV, Internet and Computer Games) and non-screen sedentary behaviours (homework and reading). Values represent adjusted associations (Beta (95 % CI)) between academic achievement (total GCSE points) and sedentary variables (hours/day) and MVPA (mins/day) 7

8 Arenor Familjebaserade interventioner Begränsat stöd van Sluijs et al 2011 Samhällsinterventioner Stor spridning i genomförande ger svårtolkad data Skobaserade interventioner Mest flyttbara mellan länder? Störst stöd (Kreimler et al 2011, Salmon et al 2007, Dobbins et al 2009) Rena träningsstudier (t ex Resaland et al 2011) ca 200 nioåringar fick en timmes Idrottsundervising om dagen i två skolår 5 minuters instruktion och 55 minuters aktivitet Bollspel ca 20% Raska promenader (ca 15 %) Lekar (12%) Skidåkning ( 11%) Gymnastik och stafetter (20%) Annat Förbättrad objektiv mätt kondition (först visat!) Tack för er tid. 8