5
Previously, we have examined the effect of posture on back pain and we have also briefly discussed some exercises and stretches that can be performed to alleviate the effects of bad posture. In this series of three articles, we will look at the effect of obesity on back problems and then explore the various ways of helping you to shed weight effectively. The spine is designed to carry the body’s weight and distribute the loads encountered during rest and activity. When excess weight is carried, the spine is forced to assimilate the burden, which may lead to structural compromise and damage. One region of the spine that is most vulnerable to the effects of obesity is the lower back and lumbar spine. Sitting for prolonged periods of time can lead to muscular imbalance, predisposing to back problems. Working for long hours and a lack of physical activity causes weight gain, especially abdominal obesity, which shifts the centre of gravity forward. This in turn leads to an increased chance of postural deviation, such as an excessive lordotic lumbar curve and anterior pelvic tilt. Such a deviation also leads to faulty loading patterns, which increase the strain on the spine and surrounding joint structures. Those with an excessive lumbar lordosis (hyperlordosis) often have a reduced range of lumbar flexion and restricted mobility, thereby increasing the risk of disc protrusion or herniation which can cause nerves to be pressed on or pinched, resulting in pain and in some cases sciatica. Are you overweight or obese? If you are overweight or obese, there are many ways of losing weight and maintaining a healthier body composition. To get started, talk with your doctor or a fitness professional to establish your ultimate goals and how to safely begin a sustainable weight loss programme. This is important because if you suffer from back pain, your exercise programme is likely to be different from someone without such problems. Remember, no two people are the same and obtaining professional help is the best initial step. Does cardiovascular exercise help you to lose weight or can it even make you fatter? Whilst physical activity is useful in reducing the risk of certain diseases, it does not necessarily promote weight loss. A person who exercises tends to cancel out the calories they have burned by eating more, generally as a form of self-reward. In order to understand the physiology of weight loss, we need to understand the relationships between diet, metabolism and the circumstances under which the body begins to burn fat as fuel. Metabolism – energy expenditure Metabolism is the sum of all the biochemical processes that occur in the body, including: Anabolism – the formation of larger molecules, and Catabolism – the breakdown of larger molecules into smaller ones. Exercise and weight loss – Part 1 – Obesity & back pain; metabolism Dr James Tang, CES, MBA, BDS, LDS RCS NASM Corrective Exercise Specialist, Level 3 Personal Trainer (REP registration no R1045463), Sports Nutritionist & Level 3 Sports Massage Therapist, with special interest in postural dysfunction and lower back problems, GDP

Back pain & obesity Part 1 - metabolism · Weight control is a matter of creating an energy imbalance, i.e., if you consume more calories than your total caloric expenditure, you

  • Upload
    others

  • View
    0

  • Download
    0

Embed Size (px)

Citation preview

Page 1: Back pain & obesity Part 1 - metabolism · Weight control is a matter of creating an energy imbalance, i.e., if you consume more calories than your total caloric expenditure, you

Previously,wehaveexaminedtheeffectofpostureonbackpainandwehavealsobrieflydiscussedsomeexercisesandstretchesthatcanbeperformedtoalleviatetheeffectsofbadposture.Inthisseriesofthreearticles,wewilllookattheeffectofobesityonbackproblemsandthenexplorethevariouswaysofhelpingyoutoshedweighteffectively.Thespineisdesignedtocarrythebody’sweightanddistributetheloadsencounteredduringrestandactivity.Whenexcessweightiscarried,thespineisforcedtoassimilatetheburden,whichmayleadtostructuralcompromiseanddamage.Oneregionofthespinethatismostvulnerabletotheeffectsofobesityisthelowerbackandlumbarspine.Sittingforprolongedperiodsoftimecanleadtomuscularimbalance,predisposingtobackproblems.Workingforlonghoursandalackofphysicalactivitycausesweightgain,especiallyabdominalobesity,whichshiftsthecentreofgravityforward.Thisinturnleadstoanincreasedchanceofposturaldeviation,suchasanexcessivelordoticlumbarcurveandanteriorpelvictilt.Suchadeviationalsoleadstofaultyloadingpatterns,whichincreasethestrainonthespineandsurroundingjointstructures.Thosewithanexcessivelumbarlordosis(hyperlordosis)oftenhaveareducedrangeoflumbarflexionandrestrictedmobility,therebyincreasingtheriskofdiscprotrusionorherniationwhichcancausenervestobepressedonorpinched,resultinginpainandinsomecasessciatica.Areyouoverweightorobese?Ifyouareoverweightorobese,therearemanywaysoflosingweightandmaintainingahealthierbodycomposition.Togetstarted,talkwithyourdoctororafitnessprofessionaltoestablishyourultimategoalsandhowtosafelybeginasustainableweightlossprogramme.Thisisimportantbecauseifyousufferfrombackpain,yourexerciseprogrammeislikelytobedifferentfromsomeonewithoutsuchproblems.Remember,notwopeoplearethesameandobtainingprofessionalhelpisthebestinitialstep.

Doescardiovascularexercisehelpyoutoloseweightorcanitevenmakeyoufatter?Whilstphysicalactivityisusefulinreducingtheriskofcertaindiseases,itdoesnotnecessarilypromoteweightloss.Apersonwhoexercisestendstocanceloutthecaloriestheyhaveburnedbyeatingmore,generallyasaformofself-reward.Inordertounderstandthephysiologyofweightloss,weneedtounderstandtherelationshipsbetweendiet,metabolismandthecircumstancesunderwhichthebodybeginstoburnfatasfuel.Metabolism–energyexpenditure

Metabolismisthesumofallthebiochemicalprocessesthatoccurinthebody,including:• Anabolism–theformationoflargermolecules,and• Catabolism–thebreakdownoflargermoleculesintosmallerones.

Exerciseandweightloss–Part1–Obesity&backpain;metabolism

DrJamesTang,CES,MBA,BDS,LDSRCSNASMCorrectiveExerciseSpecialist,Level3PersonalTrainer(REPregistrationnoR1045463),SportsNutritionist&Level3SportsMassageTherapist,withspecialinterestinposturaldysfunctionandlowerbackproblems,GDP

Page 2: Back pain & obesity Part 1 - metabolism · Weight control is a matter of creating an energy imbalance, i.e., if you consume more calories than your total caloric expenditure, you

Thebody’srateofenergyexpenditureisthemetabolicrate,andthetotalcaloricexpenditureistheproductofanumberofinteractingfactors:

• Basalmetabolicrate(BMR)isthetotalsumofallthereactionsthatoccurinthebodywhenatcompleterestwithnodigestionoccurring.Thisisusuallyexpressedasthenumberofcaloriesneededtosustainbasicfunctioning.

• Thermiceffectoffood–theamountofenergyexpendedbythebodythroughtheingestion,digestion,absorption,utilisationandstorageoffood.Thisaccountsfor6–10%ofdailyenergyexpenditureformenand6–7%forwomen(Poehlman,1989).

• Thermiceffectofactivity–theamountofenergyrequiredforplannedandunplannedlevelsofphysicalactivities.Thisisthemostvariablecomponentofenergyexpenditureanditaccountsforapproximately20–40%oftotalenergyexpenditure.

Metabolicrate=BMR+thermiceffectoffood+thermiceffectofactivity

1gofthesedifferentfoodcomponentsproducesthefollowingenergyvalues:

• Carbohydrate4kcal• Fat9kcal• Protein4kcal• Alcohol7kcal

Weightcontrolissimplyamatterofcreatinganenergyimbalancewhichforcesyourbodytoburnfatstoresforenergy.Theenergybalanceequationrequiresconsiderationofbothenergyintake(foodanddrink)andenergyexpenditure(basalmetabolicrate,thermiceffectoffoodandphysicalactivity).Insimpleterms,ifyouconsumemorecaloriesthanyourtotalcaloricexpenditure,youputonweight.Ifyouexpendmorethanyouconsume,youloseweight.Forthepurposeofweightloss,onlymacronutrients(carbohydrates,proteinsandfats),whichareusedtofuelbodyactivities,willbeconsideredhere.Itisimportantthatyoumaintainabalanceddietwhichincludestherecommendedlevelsofmicronutrients(vitamins,minerals)aswell.

Theeatwellplatehighlightsthedifferenttypesoffoodthatmakeupourdietandshowstheproportionsweshouldeatthemintohaveahealthy,balanceddiet.

Page 3: Back pain & obesity Part 1 - metabolism · Weight control is a matter of creating an energy imbalance, i.e., if you consume more calories than your total caloric expenditure, you

Source–Gov.uk

It’sagoodideatotrytogetthisbalancerighteveryday,butyoudon’tneedtodoitateverymeal.Youmayfinditeasiertogetthebalancerightoveralongerperiod,aweekforexample.Wheneverpossible,trytochooseoptionsthatarelowerinsalt.

EnergyIntake

Carbohydratesarestoredasglycogeninthemusclesandliver.Thereisapproximatelythreetimesmoreglycogenstoredinthemusclesthanintheliver.Increasingyourmusclemasswillalsoincreaseyourstoragecapacityforglycogen.Onaverage,thetotalstoreofglycogenisabout500g,equivalentto1600–2000kcal,enoughtolastadayifyouweretoeatnothing.Thisiswhyalow-carbohydratediettendstomakepeoplelosequitealotofweightinthefirstfewdaysandthisweightlossisalmostentirelyduetothelossofglycogenandwater.Onaverage,youhaveenoughintramuscularglycogentofuel90–180minutesofenduranceactivity;thehighertheintensity,thefasteryourmuscleglycogenstoreswillbedepleted.Thegreateryourpre-exercisemuscleglycogenstore,thelongeryouwillbeabletomaintainyourexerciseintensityanddelaytheonsetoffatigue.However,otherfactors,includingariseinconcentrationofthebrainchemicalserotonin,willcauseyoutofatigue.TheGlycaemicIndex(GI)isthespeedatwhichyoudigestfoodandconvertitintoglucose.Glucosehasaglycaemicindexof100.Ifyouneededtogetcarbohydrateintoyourbloodstreamandmusclecellsrapidly,e.g.,immediatelyafterexercisetoreplenishyourglycogen,youwouldchoosehighGIfood.Itis,however,notadvisabletoeathighGIfoodbeforeexercise.Whenglucoselevelsarehigh,largeamountsofinsulinareproduced,whichshuntstheexcessglucoseintofatcells,leadingtotransienthypoglycaemia.ThesafeststrategyistoconsumelowGIfoodpre-exerciseandthentopupwithhighGIcarbohydrateduringexercise.Tooptimiseglycogenstorageandminimisefatstorage,aimtoachieveasmallormoderateglycaemicload–eatlittleandoften,andavoidoverloadingoncarbohydrates.Thereis,however,noneedtocutouthighglycaemicfoods.Thekeyistoeatthemwithproteinand/oralittlehealthyfatwhichputsabrakeonthedigestiveprocess,slowingdownthereleaseofglucose.

Page 4: Back pain & obesity Part 1 - metabolism · Weight control is a matter of creating an energy imbalance, i.e., if you consume more calories than your total caloric expenditure, you

Apples(despitecontainingsimplecarbohydrates)produceasmallandprolongedriseinbloodsugar.Agreatdealofstarch-richfood(complexcarbohydrates),suchaspotatoesandbread,isdigestedandabsorbedveryquicklyandcausesarapidriseinbloodsugar.Ifyoutrytoloseweightbycombiningalow-caloriedietwithalengthycardioworkout,youareheadingfordisaster.Thisisbecausenotonlydoesyourbodyadaptsoyouhavetodomoretogetthesameresult,butaslow-caloriedietstendtobelowincarbohydrate,onceyouhaveusedupyourintramuscularglycogen,thebodystartstometaboliseproteinforenergy.So,notonlyareyounotlosingfat,youarealsolosingmusclemass.Thisisbadnewsbecausewhilstwethinkthatweexpendmostofourcalorieswhenweareexercising,mostofourenergyisusedupjustexisting–evenifyoudonothingfor24hours,youwouldstillbeburningnearly1,700caloriesinaday(basalmetabolicrate),andthemoremusclemasswehave,themorecaloriesweburn.

Fatisstoredasadiposetissueinalmosteveryregionofthebody.Asmallamountoffat,about300–400g,isstoredinmusclesasintramuscularfat.Themajorityisstoredaroundtheorgansandbeneaththeskin.Peoplewhostorefatmostlyaroundtheirabdomens(theclassicpot-bellyshape)areknowntohaveahigherriskofheartdiseasethanthosewhostorefatmostlyaroundtheirhipsandthighs(pearshape).Youcannotdoanythingaboutthewayyourbodydistributesfat,butyoucanchangetheamountoffatthatisstored.Femalehormonestendtofavourfatstoragearoundthehipsandthighswhilstmalehormonesencouragefatstoragearoundthemiddle.Thereisnoexercisethatcan,onitsown,removeyourabdominalfatanditisamisconceptionthatabdominalcrunchesandsit-upswilleradicateyourabdominalfat.

Proteinismainlyusedasabuildingmaterialratherthanasanenergystore.Proteins,however,canbebrokendowntoreleaseenergyifneedbe.Proteinisonlyusedduringveryprolonged(usuallyexercisesthatlastinexcessofanhour)orveryintenseboutsofexercise,whenglycogenstoresbecomedepleted.Somepeoplethinkthatiftheydepletetheirglycogenstoresbyfollowingalow-carbohydratediet,theywillforcetheirbodytobreakdownmorefatandloseweight.Thisisnotalwaysthecase,aswehavementionedabove,asyourisklosingmuscleaswellasfat.Exercisetriggerstheactivationofanenzymethatoxidiseskeyaminoacidsinthemuscle,whicharethenusedasafuelsource.Thegreatertheexerciseintensityandthelongeritsduration,themoreproteinisbrokendownforfuel.Therefore,ifyouarefollowingaweightlossprogramme,donotreduceyourcarbohydratetoodrastically;otherwise,proteinwillbeusedasanenergysourcemakingitunavailablefortissuegrowth.Ahigherproteinintakecanoffsetsomeoftheassociatedmuscle-wastingeffects.SoyproteinisolatehasthehighestconcentrationofthekeyaminoacidsthatareimportantformusclegrowthBCAAs(leucine,valineandisoleucine),glutamineandarginine.Thebioavailabilityofaparticularproteinisoftenmeasuredbyitsbiologicalvalue(BV)andanegghasaBVof100.Wheyproteinsareextractedfromcurdledmilk.TheyhaveaBVofupto159,whichisconsiderablyhigherthananegg.

Page 5: Back pain & obesity Part 1 - metabolism · Weight control is a matter of creating an energy imbalance, i.e., if you consume more calories than your total caloric expenditure, you

SummaryWeightcontrolisamatterofcreatinganenergyimbalance,i.e.,ifyouconsumemorecaloriesthanyourtotalcaloricexpenditure,youputonweight.Ifyouexpendmorethanyouconsume,youloseweight.Inthenextpart,wewilltakealookatthephysiologyofhowthebodyburnsfatasafuelandhowwecanoptimisefatburninginaholisticweightlossprogramme.

Ifyouhaveanyquestions,[email protected]