p h y s io th e ra p y , M a rch 1983, v o l 39, n o 7 7 EXERCISE IN THE REHARILITATION OF CHD PATIENTSf T. Noak es M.B. Ch.B. M D (UC T )* SU M M A R Y The a u th o r sets o u t to sh o w w h y cardiac p a tie n ts s h o u ld fo llo w an exercise re gim en a n d th a t th e im p o rta n t p sy c h o lo g ic a l b e n e fits a c h ie v e d b y an exercise re h a b ilita tio n p r o g r a m m e relate to the h e a lin g co n ce p t - to m a k in g the p a tie n t w hole again. In a d d itio n the cap a city f o r p h y sic a l w ork increases as d o e s th e “a n gina thre sh o ld ". The sa fe ty o f the p a tie n t is e n su re d b y p re sc rib in g exercise b a se d on results o f the target heart rale concept. F inally th e a u th o r d e fe n d s w alking a n d jo g g in g as the id ea l m o d e o f exercise. I n t r o d u c t i o n In the past de cad e a wealth o f i n f o r m a t io n has a cc um ul ate d sho win g th at following heart a tt a c k or c or on ar y ar te ry bypass surgery, cardi ac p a ti e n ts derive specific benefits fro m carefully prescribed p r o g r a m m e s of gr a d ua te d exercise (Poll ock , M. L. a nd S c hm id t, D. H. (1979)). Such p r o g r a m m e s consist ideally o f t hr ee se pa rat e phases:- • the a cu t e in-h osp ital ph ase beginning as s o on as the patient is ad m i t te d to a hosp it al Intensive C o r o n a r y Car e Unit with ac ut e m y oc a rd ia l infarction; • a hospi tal -b ase d p r o g r a m m e in which mild, grad ed exercise usually involving circuit t rai ni ng on a p p a r a t u s is pe rfo rm ed in a hospi tal ou t -p at i en t d e p a r t m e n t and; • pa rti ci pa tio n in a m ore vigorous, c o m m u n i ty - b a se d exercise p r o g r a m m e co m m e n ci n g so m e 9-12 weeks af ter m y oc a rd ia l infarction. T hi s a r t i c l e will c o n c e n t r a t e sp e c if i c a l ly o n th e m et ho dol ogy a n d p h ilo s o ph y o f c o m m u n i ty -b a s e d exercise re habilitatio n p r o g ra m m es . It is the a u t h o r ’s c o n te n t io n that medical ig nor anc e of, a n d indeed fr an k disinterest in the value such p r o g ra m m e s can play in the psychol ogical a n d physiological rep air o f ca rd ia c pati en ts ( P o ll oc k, M. L. an d Schmidt, D. H. (1979); Ka va na g h, T. a n d No a ke s , T. D. J 1979)), re ma ins a m a j o r reas on why the medical care of such (patients m ay be less t h a n o pt im u m . WHY C A R D IA C P A T IE N T S D O NO T E X E R C IS E , A N D WHY THEY S H O U L D The mo st likely reas on w hy m os t patie nts d o not exercise after he art a tta ck , is th at they either receive no advice to exercise o r they are specifically advised ag ain st exercising by their doc tor s. T he ra tio nal e be hind either o f these a pp ro ac h es has been defined a n d discussed ( N oa k es , T. D. (1982)). In essence, exercise a fte r h e a rt -a t t a c k is held to be too d a n g er o u s, t o o expensive a n d o f no pr ove n benefit. In a ddi ti on it is a rg ued th a t th ere are no medical pe rso nne l to spare on the surviv ors o f h e ar t- at ta c ks , be cause such t R e p r i n t e d by p er mi ss io n o f SA Sp o rt s Medicine. ‘ C o n v e n o r o f p o s t - g r a d u a t e sp o r t s science course. M e tr op ol it an S p o r t Science Ce ntr e D e p a r t m e n t o f Medicine, University o f C a p e T o w n O P S O M M IN G D ie s k r y w e r m ts aan w aarom hart p a s ie n te 'n o e fe n p ro g ra m m o e t v olg en d at die b ela n g rik e s ie lk u n d ig e v o ordele b e h a a l d eur in oefe n re h a b ilita siep ro g ra m in v er b a n d sta a n m e t die h e lin g sk o n se p - o m die p a sie n t weer h e el te m a a k . D aarbv verm eerd er die fisiese w e rk sk a p a site it, a s o o k die ‘‘angina d rem pel". D ie veilig h e id van die p a sie n t w o rd v erseker d eur oefening, gebaseer op die resultate v an die “m ik p u n t h art slag k o n se p ". Ten slo tte verdedig die sk r y w e r slap en p r e td r a fa s die ideate m e to d e van oefening. pe rso n ne l are a lr e ad y t o o busy l o o ki n g after the acutely-ill. E ach o f these criticisms has been d e b u n k e d elsewhere (Noa kes , T. D. (1982)) a n d will t he re fo re n o t be restated. Suffice it to say th at su ch criticisms may reflect a serious malaise o f m o d e r n medicine — na m e ly its m o n o p o li z a t i o n by so-called “curat ive medicine” to the tota l ex clusion of preventive a n d rehabilitative medicine. One i m p o r t a n t result is th at o u r m o d e r n “scientific” a p p r o a c h to the ev alu ati on of a novel t h er a p eu ti c inter ven ti on, such as exercise, is to evaluate th a t inter ven ti on exclusively on the basis of w he th er or no t it plays a curative role in a specific disease process. T h u s we d e m a n d th at t h er e mu st always be a scientifically- testable e n d p o in t ag ain st which a n y new inte rv en ti o n must be eval uat ed ; in the case o f exercise a fte r h e ar t- at ta c k, such exercise mu st be show n to reduce the re-infarction ra te an d increase longevity. As long as these rema in the sole criteria for ev alu ati o n, then the role th at exercise can play in the re h ab ili ta ti o n o f cardi ac pati en ts will never be fully app rec iat ed. F o r the simple reason th at this “scientific” a tt i tu d e runs quite c o n t r a r y . t o wha t sho ul d be a n inviolate medical a tt i tu d e name ly t h a t medicine is as m u c h the a r t o f healing as it is the science o f curing. With regard to c o r o n a r y heart disease, there is as yet no p r ov en m et h o d by which the p r i m a r y pa tho lo gi cal process in this disease, c o r o n ar y ath er osclerosis, can be reversed. N o r is th ere any k n o w n m e th od by which the infarcted m y o c a r d iu m c an be restored. T h u s m o d e r n medicine has little science with which to cure this disease a n d it is th erefore illogical to expect th a t exercise can achieve this. W h at exercise r eh abi lit ati on achieves' for the card iac pati en t relates to the t h r ea te n e d medical ar t o f healing. Healing is the t rea tin g o f the p a ti e n t ’s illness, which is simply the m en ta l response to the disease. Healing is the a r t of de creasing sy m p t o m s , o f e n h an c in g the p a ti e n t ’s sense of physical a n d ps ychological well-being, of rest or ing the whole person. Unf or tu n ate ly , these chang es are no t easily, n o r frequently, mea sur ed . Th ey do n o t sho w on bl ood tests, on c h e s t X - r a y s , o n c o r o n a r y a n g i o g r a m s , o n ele ct ro c ar d io gr am s, o r even on tests o f h e ar t function. Yet we w o u ld be wr on g to as su m e th at these i m p o r t a n t changes do not o c cu r in exercising car di ac patients. F o r it m ay be that the exercise r eh abi lit ati on o f the car di ac patient achieves two benefits th at no d o c t o r a n d no bo ttl e o f pills can. First, exercise rehabi lit ati on m ak e s the pa tie n t an active and a w a r e p a r ti c i p a n t in his ow n recovery. C o r o n a r y disease is believed to be a lifestyle disease a n d successful R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) 8 F isio te ra p ie , M a a rt 1983, d e e l 39, n r 1 re h ab ili ta ti on m us t aim to alt er the negative aspects o f each pa tie nt ’s lifestyle. No physic ian c an legislate an altered lifestyle for his pa tient. T he only pe rso n w ho c an successfully achieve th at is the pa tient. But if the pa tie nt ch ooses to r e m a in a pi ll- pop pi ng sp ec tato r, wh o co nt in u es to sm o ke heavily, wh o c on tin u e s to eat incorrectly a n d w h o conti nue s to wo rk excessively, his pr og no sis mu st r e m a in grave. W h a t the c or rec t exercise r e h ab ili ta ti o n p r o g r a m m e does then , is to alte r the pa ti e n t ’s self co ncept. It teaches him that he must l oo k a fte r his b o d y in the sam e way th a t the athlete does. He m us t con sid er ho w his daily ha bits affect his physical a nd m en ta l pe rfo rm an ce. F o r tu na te ly , regular exercise pr ov id es imm ed iat e, daily feedback. If the patient over-indulges in a n y of the de tr i m en t al lifestyle pur suits described ab ov e, they will adversely affect his exercise capacity. Sec ond, exercise trai nin g shows the patient th a t he is not physically crippled. A f u n d a m e n ta l c o m p o n e n t of his disease is th at the ca rd ia c pati en t views his disease as a physical, not a psychological disability. T h u s the psyc hological tr a u m a that the pati en t experiences a fte r a heart a tt a ck , relates mostly to his fear th a t his he art a tt a c k has left him physically i n cap aci tat ed (C as se m , N. H. a nd H ack et t, T. P. ( 1977)). The pa tie n t kn o w s t h a t to live a nd w o r k c o m f o r t a b l y he must have a cer tai n degree of m yo ca rd ia l integrity a n d a certain level of physical fitness. But exercise is the sole “ test” th a t will sho w the pa tie n t th at he is not a physical cripple. In co nt ra st, if the pa tie nt do e s no t exercise o r is con fined to bed for any length o f time, his physical fitness will de ter ior at e, a nd he will in correctly inte rp ret this fall in physical fitness as evidence of im p ai red heart fu n cti on (Cassem, N. H. and Ha cke tt T. P. (1977)). Th is was the universal o u t c o m e o f the o u t d a t e d six week s’ bed rest t re a tm e n t for m yoc ar dia l in far cti on ( K a v a n a g h . T a n d No akes, T. D. (1979)). In su m m a r y , the i m p o rt a n t psyc hological benefits achieved by a n exercise re ha b ili ta ti o n p r o g r a m m e relate to the healing c o nc e p t — to m a k i n g the pati en t whole again. It must be e m ph a si ze d th at the specific psychological benefits derived f ro m exercise re h ab ili ta ti on are sufficiently i m p o r t a n t by themselves to justify a n exercise r e hab ili tat io n p r o g ra m m e . But o t h e r i m p o r t a n t benefits d o exist. A L T E R A T IO N S IN W ORK C A P A C IT Y A N D THE “A N G IN A T H R E S H O L D ” Physical w o r k c ap aci ty is increased in vi rtually all e xer cis e-rehabilitated card iac patients, with the most i m p o r t a n t benefit being an a lte ra tio n in the an gi na threshold. Exercise t r ai ni ng m ar k e d ly increases the a ng in a th res hol d so th at a f te r training, m o re intensive exercise can be pe rfo rm e d before a n g in a occurs. T he m ec h an is m fo r this increase in the a n g in a t hre sh old is p r o b a b ly due no t to increased bl ood flow to the a re a of j e o p a rd iz e d (ischaemic) m yo ca rd iu m ( F e r g u s o n el at. (1978)). R a t h e r it is d u e to a r e du ct io n in the exercising heart rate a n d b lo od pressure, and there for e in m yo ca rd ia l oxyge n d e m a n d , med ia ted by a d a p t a t i o n s specific to the tr ain ed, skeletal muscles (Cl ausen J. P. (1976)). T h e result is that, at the sam e ex ter nal w o rk lo a d (i.e. walk ing o r j o g gi ng speed), the w o r k o f the he art (m ea su re d as the he art r a t e / b l o o d pres sur e p ro d u c t) is reduced. T h e r e fo r e the a n g in a t hr esh old will increase, but because this is d u e not to car di ac a d a p t a t i o n s , bu t principally t o p e rip he ral changes, this increase will only be a p p a r e n t d ur i n g exercise with the train ed muscles. Th is “ specificity of trai n in g” indicates t h at pa tie nt s with a n g in a must , in the first instance, be t rai ned in the same exercise m o d al i ty th at causes them ang ina . In most cases, this will be walking. S U B S E Q U E N T M O R T A L I T Y O F C A R D I A C P A T IE N T S U N D E R G O IN G E X E R C IS E R E H A B IL IT A T IO N T w o p ro b l em s cloud the qu e sti on o f w h e t h er o r not exercise trai nin g influences sub se q ue n t m or ta lit y in c o r o n a r y p a ti e nt s ( S h e p h a rd , R. J. (1979)). First, most re h ab ili ta ti o n studies d o not c o n ta i n a d e q u a t e co nt ro l g r o u p s — th at is, pati en ts are no t ra n d o m l y assigned to an exercising or to a c o n tr o l g r ou p . R a th e r the mor tal ity ex perience in the exercising g r o u p is c o m p a r e d to m o rta lit y in a “c o m p a r a b l e " grou p. Sec ond , those re h ab ili ta ti on p r o g r a m m e s which have had a d e q u a t e ra n d o m i z e d c on tr o l gr ou ps, have either used relatively h o m e o p a t h ic exercise doses o r have had a p o o r exercise c o m pl ia nc e record. T o c om p li ca te the issue, the “ non-e xer cis ing” c o n tr o l ca rd ia c gr o u p has frequently become pollute d with card iac patie nts w ho take up exercise o f their ow n ac c o rd (Sha w, L. W. (1981)). Despite these limi tations, it is possible to sta te th at • in virtually every re p or te d study, the m o rta lit y r a t a m o n g s t exercising cardi ac patie nts is less t h a n in th e- c o n tr o l gro u p , • in no studies is m o rta lit y rate in the exercising g r o u p g re a t e r th an in the c o nt r ol gro u p , • studies th at have failed to sho w a ny benefit for the exercising g r o u p have used a low intensity exercise, have been as soc iated with a high d r o p - o u t rate a nd have been o f sh o r t d u r a t i o n (less th a n 2 years). T h u s the mo st recent d a t a suggests th at differences in m o r ta lit y rates between exercising a nd co n tro l c ar d i ac pa tie nt s be com e m or e m a r k e d a fte r 2 years o f fairly intensive trai nin g ( S h e p h a rd , R. J. (1979)). How ever, m o r e recent studies have pro vi ded more o ptimi stic results. T h u s in a carefully c o ntr ol led st u dy Kallio el al (1972) show ed a n alm ost im m e d ia te re d u ct io n in the c o r o n a r y m o r ta lit y of c ar d i ac pati en ts a d m i t te d to an intensive e d u ca ti o n a l/ e x e r c is e re h ab ili ta ti on p r o g r a m m e a fte r their first heart atta ck. T h e recently r e po rte d Na tional Exercise a nd He art Disease Proje ct (S ha w, L. W. (1981)) fo un d evidence for a “ sub sta nt ial benefit f r om exercise” after heart a tt a ck , an d K a v an a g h el aI (1979) re po rte d that pa tie nt s w ho failed to c o m p l y with a n exercise re ha b ili ta ti o n p r o g r a m m e a fte r heart a tt a c k had a 22-fold higher incidence of re cur re nt m y o ca rd ia l in farction o r c o r o n a r y m o rta lit y t h a n did thos e w ho c o n tin ue d to exercise. Th er e was evidence th a t this re m a r k a b l e difference could be e x p l a i n s ^ on the basis that the most disabled pa tien ts, at high risk of recurre nce , were t o o ill to c o m p l y with the p r o g r a m m e . The r e ason s why these pati en ts failed to c o n tin u e in the exercise p r o g r a m m e ha d n o t h in g to d o with pro gr ess io n o f their disease. But despite these co ns id er a tio ns , my pe rso n al impre ss ion is th at ca rd ia c patie nts in a n exercise re h ab ili ta ti on p r o g r a m m e are no t greatly co nc e rn ed a b o u t q ue st ion s of longevity. As one card iac pati en t said: “ I’m not j o g g in g to live longer. I’m j og gin g because it’s m a d e me fit, a n d 1 can now enjoy cer tai n pleasures in life th a t have always been i m p o r t a n t to me. 1 no longer have a n g in a w he n I stay up late at night, a n d 1 can play longer a n d h a r d e r t h a n ever before, a nd for me t h a t ’s wha t living is all a b o u t ” . I N S U R IN G T H E S A F E T Y O F T H E C A R D I A C P A T IE N T D U R IN G E X E R C ISE T h e r e m a r k a b l e sa f e t y o f e x e r c is e r e h a b i l i t a t i o n p r o g r a m m e s is not a c ha n c e event. N o r ha s it been easily achieved. It has resulted f r o m care ful a tt e n ti o n to cert ain R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) p h y s io th e ra p y , M a rch 1983, v o l 39, n o 1 9 guidelines that have been established over the years. The following guidelines are those used by the Wes ter n Cape Card iac R e ha b i l it a t i o n P r o g r a m m e a n d are based o n the a p p r o a c h de veloped by Dr. T er r y K a v a n a g h in T o r o n t o (Ka va na gh , T. a n d Noa kes , T. D. (1979); K a v an a g h T (1976)). Before a c ar d i ac pa ti e n t is e xp o se d to a r e gu la r exercise pr o g r am m e, it is essential th a t he u n d e r ta k e a medically- supervised, e le c t r o c ar d io gr ap h ic al ly -m on ito re d , progressive exercise (stress) test on eit he r a bicycle e r g o m e te r o r a treadmill. There are two reaso ns for this. First, the test will identify those pa tie n ts for w ho m for mal exercise trai n in g is co n tra in d ic ted , eit he r because they have a d va n c ed left ventri cul ar d a m a g e or, p e n d in g th er a py , because they develop serious card iac a r r h y t h m i a s d u ri n g exercise. Second, the test will identify the a p p r o p r i a t e exercise level for each patient. T he following is o u r a p p r o a c h to exercise testing. Patients w ho d o no t have a ny o f the described c o nt r a in d ic at io ns to exercise testing (Po ll oc k, M. L. an d Schm idt, D. H. (1979)), are exercised on a treadmill a cco rdi ng to eit he r the N a u g h t o n or Balke p ro to co l. Both these pr ot oc ol s are of lower intensity t h a n is the Bruce protocol, which we feel progresses t o o rap idly for card iac patients. D u ri ng the exercise test, the following p a r am et e r s are mo n ito re d an d record ed every minute; bl ood pressure via an a u to m a te d system ( C r i ti k o n In c o rp o r a t e d , T a m p a , Florida), heart rate (displayed digitally), a n d the e le ct r oc ar d io gr am recorded in 3 leads a nd displayed co nt i n u o u sl y in one lead, with a digital r e a d o u t o f S T levels an d S T slopes in th at lead ( M a r q u e t t e C a s e s y s t e m ; M a r q u e t t e E l e c t r o n i c s , Milwaukee, Wisconsin). In a d di t i on , the pati en t is carefully observed for signs, a n d is a ske d each m inu te to describe his level o f perceived exe rtion (Borg, G. (1970)) a n d the na ture of any sy m p to ms . Re sp i r at o r y gases are not anal yze d du ri ng the initial test, b e c a u s e th e y only cause a d d i t i o n a l a n x i e t y f o r the patient a n d do not provi de essential in fo rm a tio n. The exercise test is te rm in at ed whe n one o f the following e nd- po int s is reached: • if 85-90% o f the m a x i m u m he art ra te pred icted for age is achieved w i t h o u t the pati en t d e v e l o p i n g e i t h e r s y m p t o m s or signs of m y oc a rd ia l ischaemia (un c om pl ica te d m a x i m u m test), • if the pati en t develops charact eri sti c a n g in a pectoris (with or w it ho u t c o m p a t ib l e e le ct ro c ar di og r ap hi c changes), and • if there is depr ess ion o f the S T segment in a n y o f the three m o ni to r e d leads which is either h or izo nt al o r d o w n w a r d sloping, a n d in excess of 2 m m , 80 milliseconds a ft e r the J point. In card iac pati en ts this degree o f ST segment depres sio n is highly predictive o f multi-vessel disease, it indicates increased risk of a fu r t h e r ca rd ia c event, a n d is m or e likely to be fo u n d in p a ti e nt s w ho hav e ha d previous inferior, r a th e r t h a n a n t e r i o r m yo ca rd ia l in farction (Castellanet et aI (1978); Paine el a t (1978)). • failure of either the systolic bl ood pressure or he art rate to increase a p p r o p ri a te l y d u r i n g exercise o f increasing intensity. Failu re o f the systolic blood pressure to rise (ino tro pi c i n co m pe ten ce) is ass ociated with exercise- in duced v e nt ri cu la r fibrillation (Irving, J. B. a n d Bruce, R. A. (1977)) a n d a very p o o r overall pro gno sis (Irving, J. B. a n d Bruce, R. A. (1977); Irving et al (1977)) • a pp e a r a n c e of ve n tri cu la r tac h yc a rd ia , intr a ca rd ia c block or ve nt ri cu la r p r e m a tu re beats (in excess o f 25% of all beats). • signs of excessive fatigue or dyspno ea . On the basis o f the exercise test result, it is possible to d ete rm in e • w h e th er the pati en t is a c a n d i d a t e for a n exercise re h ab ili ta ti o n p r o g r a m m e o r alt ernatively, w h e th er he sh oul d be referred for fu r th er car diological eval uat io n, an d • at wha t h e ar t rate it is safe f o r each p a ti e n t to exercise. P R E S C R IB IN G E X E R C ISE ON THE B A S IS OF THE E X E R C IS E T EST R E S U L T S - THE T A R G E T H E A R T R A T E CO NC EPT In o r d e r to achieve a t r ai ni ng effect, the exercise prescri pt ion mu st be o f the co rrect intensity (h o w fast), d u r a t i o n (how long), frequency ( h o w often) a nd it mu st be specific to the required goals. At present, we a p p r o a c h these fo u r categories in the following m ann er . Frequency and duration C u r r e n t evidence suggests t h a t card iac pati en ts should train for between 3 to 5 ho ur s a week (i.e. I ho u r, 3 to 5 times a week), de p en d in g on how h ar d they exercise. Intensity U nd o u b t e d ly the mo st critical decision conce rn s the intensity at which each card iac patient sho ul d exercise. Because the severity of c o r o n a r y he art disease differs in all patients, the intensity at which each is able to exercise safely will ob vi ous ly vary. T h u s the p re sc ri p tio n of the trai nin g intensity mu st be carefully individualized for each patient. Figures I a n d 2 illustrate one a p p r o a c h to this pro bl em. TR A IN IN G ZO N E C O N C EPT Fig. 1. With age, there is a predictable fall in m axim um heart rates. To achieve an aerobic training effect, it is believed that the exercising heart rates should be between 60 and 90% o f m axim um . R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) Figur e l show s th at with age there is a pre dic tab le fall in m a x i m u m a tt a in a b le heart rate from a value of a bo ut 200 at age 20, to a b o u t 150 at age 70, It is also k n o w n th a t to achieve an aer obi c t ra in in g effect, the trai nin g intensity must be between 60 a n d 90% o f the predicted m a x i m u m heart rate. He art rates th at fall between these two values const itu te “tra in in g zon e h e ar t rates". In n o r m a l healthy individuals it is a simple m a t t e r to predict each ind ividu al’s trai ni ng heart rate zone on the basis o f his age. But in ca rd ia c pa tien ts, w it ho ut p ri o r exercise testing, it is quite impossible to predict these trai ni ng zon e heart rates, because c o r o n a r y heart disease has a totally un pr ed icta b le effect on the m a x i m u m achievable he art rate. Thus m a x i m u m he art rates in a 40 year old ca rd ia c pati en t may. for ex ample, be a n y th i n g between 90 a n d 180 b e a t s / m in . 10 SAFE EXERCISE IN TEN SITY FROM ECG R ESPONSE Fig. 2. This figure sh ow s how the cardiac patient's electrocardiographic and sym ptom atic response to an exercise test is used to determine the intensity at which he can exercise. In this hypothetical exam ple, mild angina pectoris and 2 mm electrocardiographic ST segm ent depression occurs at a heart rate o f 150 b eats/m in . By exercising at between 60 and 90% o f this maximum heart rate (150 b e a ts/m in ), not only will the patient’s safety be assured, but the intensity will be sufficiently high to achieve a training effect. Figure 2 sh ow s how, fro m the results o f a n exercise test, the t rai ni ng zone he art rates can be established in the card iac patient. In th a t figure, which is based on an hypo th eti cal test, the e le ct r o c ar d i o g r am was m o n it o r e d d u r in g a progressive treadmill exercise test co nsisting o f 3 m inu te w or k stages. Blood pressure ( n o t sho w n) was m o n it o r e d every min ute a n d in this hy pot het ica l case, the response was n or m al , falling in the up pe r zon e p o r t r a y e d in Figure 3. It will be n o te d th at in the second exercise stage (b etween 3 a nd 6 minutes), e le c t r o c ar d io gr ap h ic S T se gment depr ess ion F isio te ra p ie , M a a rt 1983, deeI 39, n r 1 W O R K L O A D S S ub m axim um Fig. 3 During dynamic exercise o f increasing intensity, systolic b lood pressure should increase as shown in the upper shaded area o f this figure. Failure o f the systolic blood pressure to rise normally during a progressive exercise test indicates severely com prom ised heart function and is an absolu te indication to terminate the exercise test without delay. D ata after W olthuis et ah Circulation 1977, 55, 153-157. of 0.5 m m is first n ot ed at a heart rate of a p p r o x im a t e ly 112 b e a t s / m in . This progresses to 1 m m S T seg men t de pression at a he art rate of a b o u t 135 be at s/ m inute, at which po i n t the pa tie n t c o m p la in s of mild, bu t distinctive, a ng in a pectoris. At a heart rate of 150 b e a t s / m i n u t e , the S T se gment d e pr ess io n equ als 2 m m and sh or tl y t h er e af t e r the patient c o m p la in s of m ar ke d ang ina , a n d the test is term in ate d. (This ill ustration shows th at S T -s e g m en t ch anges m a y precede the onset o f angina. M a n y a u th o ri tie s would advislj that a stress test sho ul d be ter m i n at ed wh en S T levels are depressed by 2 mm.) F r o m the results of this a de q ua te , sy m p to m -l im it ed m a x i m u m exercise test, it is n o w possible to safely prescribe exercise for this patient. O u r a p p r o a c h is to prescribe exercise at up to 90% o f the m a x i m u m he art rate m eas u re d d u r i n g the t rea dm il l test if the test failed to reveal an y co m pl ic a tio ns ( a b n o r m a l blood pres sur e response; significant S T seg men t d ep res si on o f 2 or m or e m m , o r a ng in a pectoris). Alternatively, if an y o f these a b n o r m a li t ie s do manifest d u r i n g exercise, t hen the m a x i m u m allowable exercising h e ar t rate is 90% o f th at hear t rate at which these ab n o r m a li t ie s a pp ea r ed . It is essential for each pati en t to pr ogress slowly up to an exercise intensity th a t elicits his m a x i m u m allow able heart rate. This is parti cul ar ly necessary to p re ven t the d ev el o p m en t o f o r t h o p a e d ic pr obl em s. Th ere fo re, for the first 2 weeks on the p r o g r a m m e , pati en ts exercise at only 70% of th eir m a x i m u m allo wa bl e h ear t rates. Th erea fter, they are allowed to exercise at up to 80% of their m a x i m u m heart rate for a fu r t h e r three to six weeks, a n d only there aft er are they allowed to exercise at up to 90% o f m a x i m u m . R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) p h y s io th e ra p y , M a rch 1983, vo! 39, n o 1 11 Patients are re-tested after 6 m o n th s ei ther if they develop sympt oms du r i n g exercise or if th eir original test did not re v e a l an y a bn o rm a lit ie s, an d the patie nt finds th at he is persistently exercising at m o r e t h a n 90% of his m a x i m u m allowable heart rate. It is o u r cu rre n t experience, consistent with the published literature, th at S T segment chang es at a p a rti cu la r heart rate are riol altered by training. T h u s a patient whos e initial test showed e le ct r oc ar d io gr ap h ic S T segm ent de pr ess io n at a particular heart ra te will, a fte r a trai ni ng period, sh ow the identical response either a t the sa m e heart rate, o r a a low er rate (indicating c o r o n a r y a rte ry disease progression). Thus the patient whose previous exercise test was a b n o r m a l an d who persistently exercises at a heart rate gr e at er t h a n his m ax im um allo wa bl e rate, is simply o v e rd oi n g it, a n d mu st be advised to reduce his exercise intensity. But the pati en t who persistently exercises at m o re t h a n his m a x i m u m allowable heart rate but w hos e previous test was n o r m a l may, on the basis o f a repeat test, be allowed to increase his exercise in tensity if, on the rep eat test, he achieves a high er m a x i m u m Tieart rate w it ho ut the de ve lo pm en t of an y abn orm ali tie s. Patient m onitoring during exercise Once the patient has been exercise tested a n d it has been established th a t there is n o t h in g to c o n tr a - in d ic at e exercise training, he or she may be ad m i t te d to a R e h ab il ita ti on P r og ra m m e which sh ou ld ideally be held th ree times a week. F o r reasons that will be discussed, mo st of the time all ocated for exercise sh oul d be spent walking, jog g in g or cycling, with other less st r e n u o u s activities pro vi di n g an occa sion al break in routine. Du ring each exercise session, careful a tt e n ti o n is paid to the following: • The pa ti e n t ’s exercising heart rate is regularly checked. At first, heart rates are m eas ur ed every few min ut es but later, as the pa ti e n t ’s ability to m o n it o r his exercise intensity improves, heart rates are m o n it o r e d only on ce every session. The pulse checks are essential to insure th a t the patient exercises at the a p p r o p r i a t e intensity. Each pati en t is carefully instructed so th at he kno ws w h a t his m a x i m u m allowable heart rate is, a n d h ow he can mea sur e his pulse. To re-inforce these practices, all patients ar e r eq ui re d to fill out an activity card at the end of each exercise session. T he card includes in fo r m a t io n on resting heart rates a n d blood Ppressures, on exercising heart rates, on distanc e covered during exercise, on the presence of sy m p t o m s , a n d any medications th at might have been taken. • A bn o r m a l heart r hy th m s mu st be c on st an tl y l oo ked for by both pa tients a nd docto rs . Patie nt s are there fo re told to report an y card iac r h y t h m abn or ma lit ies . • All s y m pt om s mu st be immediately r ep ort ed . O u r belief is that patients will de vel op w a rn in g sy m p t o m s a n d only if these s y m p t o m s are ignored, will p ro b l em s develop. Sym pt om s such as excessive fatigue, ge neral malaise and tiredness, a n d especially a ng ina -ty pe pa in mu st be ta ke n extremely seriously. T hey are an imm e di a te in di c a tio n to reduce the t r ai ni ng load, a nd for fu r th er car di ac ev aluation. • The patient is not allowed to exercise d u r i n g o r wit hin one week of a pyrexial illness due to the possible, albeit low, risk of a fatal m yoc ar dit is (K a v an a g h , T. a n d No ak es , T. D. (1979)). Patients are also told th at they must tr a i n regularly without pe aks o f activity, th at they mu st avoid c o m p e tit io n, that they must reduce their exercise t r ai ni ng load whe n either ischaemic p r o d o m a t a or m ent al tens ion a n d depres sio n develop. It is o u r feeling th at wo rk tens ion a n d business stress, pa rticularly wh en it involves travel, are i m p o rt a n t causes o f tran si en t e x a c er b a t io n o f sy m p to m s . S m o k i n g is abso lu tel y pro hi bi te d because o f its serious effect on patient pr ognosis (M u l c a h y el a! (1977)), a n d p a r ti cu l a r a tt e n ti o n is paid to patients with Type A personalities because they are n o to rio us ly difficult to c o nt r ol in the exercise rehabi lit ati on setting. They are the am b it io u s, co mpetitive, deadline- fighting ch ar a ct e rs w h o are over -ea ger to excel a n d to ‘def eat ’ th eir disease ( K a va n a gh , T. and No ak es , T. D. (1979)). They will frequently exceed th ei r exercise pres cri pt ion a n d fail to re p o rt sy m pt om s. T h u s they need p a rti cu la r att en tio n. T H E E X E R C IS E M O D E . W HY O NLY W A LK IN G A N D JOGGING? The qu e sti o n is fr equent ly asked: W hy is walking and jo gg ing the m o st fr equent ly prescribed exercise for the cardi ac pa tient? Ther e are va rious reasons for this. First, ar g u ab l y the most successful rehabi lit ati on p r o g r a m m e in the world, th at developed by K a v an a g h at the T o r o n t o R e h ab il ita ti o n Ce ntr e (K a v an a g h , T. and No akes, T. D. (1979); K a van ag h, T. (1976)) is based purely on walking a n d jogging. Yet it has o n e of, if no t the highest exercise co mp li an ce rates o f any r e h ab ili ta ti on p r o g r a m m e in the world. T h u s the m aj o r criticism agai nst the use of wal k in g/ jo gg in g, name ly th at it is “to o b o r i n g ” a n d that pati en ts will not comply with the p r o g r a m m e , has been di sprove d by the o u t s t a n d i n g success of th at pr og r am m e. Sec on d, w a l k in g / j o gg in g is n on -c om pe tit ive , its intensity can be self-controlled, it can be d o n e an ywh ere , an d do es not require expensive e q u ip m e nt or, indeed m u ch roo m. Fo r exam pl e, som e pati en ts have even learned to jo g in the n a r ro w confines o f hotel r oo m s whilst travelling. Thir d, w al k in g / j o g g in g is the exercise m ode most appli cab le to daily living. The patient can there fo re relate the exercise he per for m s in the p r o g r a m m e with the exercise re qu ire me nt s o f his daily life. He s o o n learns what activities in his daily life he can d o w it ho ut lim itation, a nd those in which he sh o ul d be m o r e cautious. F u r t h e r m o r e , because few a d u lt So u t h Africans ever do m uch wa lk in g /j og g in g , after only a few weeks’ t r ai ni ng most ca rd ia c pati en ts are able to achieve physical feats th at they have not d o n e since their child ho ods. This beco mes a s tr on g m o ti va tio n a l f act or for f ur th er impr ov em ent . F o u r t h , it seems th a t the o p t i m u m trai n in g effect an d o p t i m u m psychological benefits result when the person does (fairly) ha rd , p ro t r ac te d physical effort. It has been o u r experience that the feeling of physical ach iev em ent is far g re ate r when m or e vi gor ou s exercise, like jogging, is per for m ed . Also we feel th at th ere is a gre ater trai ni ng benefit when a p a rti cu la r set o f large muscle gr ou ps is persistently trained. In the s h o r t term, “en te r ta i n m e n t activities” like volleyball, calisthenics a n d table tennis may be acc eptable, but o u r in te r p r e t a ti o n is th at these activities in cur low rates of ox yge n c o n s u m p ti o n (Fl etcher, el al (1979)) a n d th erefore p ro b a b ly p r o d u c e little t rai ni ng benefit and p ro vi de little m ot i v a ti o n for the patient to m odify his lifestyle. In the long term , the best ho pe for the car d ia c patient would seem to be th a t he shou ld beco me “ad d ic t e d " to a p hy sic all y- dem and in g activity which will e n co u r a g e him to a d o p t a lifestyle associated with low c o r o n a r y risk. A C K N O W L E D G E M E N T S The Wes ter n C a p e C a r d ia c R e h a b il ita ti on P r o g r a m m e is r un u n d e r the auspices o f the S o u t h e r n African Na tio n a l He art F o u n d a t i o n , whose financial su p p o r t of this project is R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) 12 F isio te ra p ie , M a a rt 1983, de eI 39, n r 1 gratefully a ck n ow le dge d. T he Chris B a rn ar d F u n d has provided ge ne ro us fun di ng for the pu rc ha se of essential exercise testing e q u ip m e n t. T he p r o g r a m m e is ru n by the a u th o r , in c o n ju nc tio n with Dr. David N a t h a n F A C C , Dr. Fra ncis T h a n d r o y e n M R C P an d Sister Ther es e de Boer. Thei r e n th us ia sm a n d su p p o r t is gratefully a c k n ow le dg ed , as is the help of the c o m m itt e e of the C ap e Wes ter n Branch of the Na tio na l He art F o u n d a t i o n a nd that of Pr of e ss or Brian Kennelly, w ho or iginated this project. References Borg, G. (1970). Perceived exer tion as a n i nd ic a to r of soma tic stress. Scand. J R e h a b ii M ed., 2, 92-98. Cassem, N.H. an d Hack et t, T.P. (1977). Psychological aspects of m yo ca rd ia l infarction. M ed. d i n . N o rth A m ., 61, 711-721. Castellanet, M .J ., G re enb er g, P.S. a n d Ellestad. M. H. (1978). C o m p a r i s o n of S T se gment chang es on exercise testing with an g io g r a p h ic findings in pati en ts with pri or m yo car dia l infarction. A m . J. Cardiol., 42, 29-35. Clausen , J . P . (1976). 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