﻿168 
  Dr. 
  A. 
  D. 
  Waller. 
  The 
  Physiological 
  Cost 
  of 
  Muscular 
  

  

  Respiratory 
  quotient 
  

  

  co 
  2 
  /o 
  2 
  . 
  

  

  Calories. 
  

  

  Kilogramm 
  etres. 
  

  

  1 
  c.c. 
  C0 
  2 
  per 
  sec. 
  

   signifies. 
  

  

  1-00 
  

   0-95 
  

   0-90 
  

   0-85 
  

   0-80 
  

   0-75 
  

   0-70 
  

  

  5 
  

   6 
  

   6 
  

   6 
  

  

  o 
  

   5 
  

  

  5 
  

  

  047 
  

   ■317 
  

   •587 
  

   856 
  

   126 
  

   396 
  

   ■667 
  

  

  2-155 
  

   2 
  -270 
  

   2 
  -386 
  

   2 
  -501 
  

   2 
  615 
  

   2-731 
  

   2-846 
  

  

  21 
  -08 
  

  

  22 
  -06 
  

  

  23 
  -02 
  

   24-01 
  

  

  18 
  "17 
  Kals 
  per 
  hour.* 
  

  

  19 
  -14 
  „ 
  „ 
  

  

  20 
  -11 
  

  

  * 
  To 
  reduce 
  clerical 
  mistakes, 
  I 
  am 
  accustomed 
  to 
  write 
  " 
  cal 
  " 
  for 
  the 
  small 
  or 
  gramme 
  

   calorie, 
  and 
  " 
  Kal 
  " 
  for 
  the 
  large 
  or 
  kilogramme 
  calorie. 
  

  

  by 
  inspection 
  of 
  which 
  it 
  appears 
  : 
  

  

  (1) 
  That 
  the 
  maximum 
  error 
  between 
  the 
  extremes 
  TOO 
  and 
  - 
  70 
  is 
  

   ±13-79 
  per 
  cent. 
  . 
  

  

  (2) 
  That 
  the 
  practical 
  error 
  between 
  the 
  probable 
  range 
  - 
  90 
  and 
  0*80 
  is 
  

   + 
  4-598 
  per 
  cent. 
  

  

  I 
  have 
  allowed 
  therefore 
  as 
  inherent 
  to 
  method 
  B 
  the 
  practical 
  (probable; 
  

   error 
  = 
  +5 
  per 
  cent. 
  

  

  There 
  is 
  an 
  error 
  of 
  observation 
  inherent 
  to 
  short 
  (1 
  to 
  5 
  min.) 
  samples 
  

   that 
  requires 
  particular 
  consideration 
  at 
  this 
  stage. 
  

  

  In 
  forced 
  breathing, 
  either 
  voluntary 
  without 
  other 
  muscular 
  exertion, 
  or 
  

   involuntary 
  in 
  consequence 
  of 
  work, 
  there 
  is 
  increased 
  ventilation 
  and 
  

   increased 
  output 
  of 
  C0 
  2 
  , 
  which 
  is 
  pumped 
  out 
  of 
  the 
  pulmonary 
  alveoli 
  and 
  

   blood 
  to 
  an 
  exaggerated 
  degree. 
  It 
  is 
  difficult 
  in 
  a 
  short 
  sample 
  taken 
  during 
  

   increased 
  work 
  to 
  assign 
  the 
  shares 
  of 
  increased 
  muscular 
  action 
  and 
  of 
  

   increased 
  pump 
  action 
  in 
  the 
  total 
  increase 
  exhibited 
  by 
  a 
  short 
  sample, 
  

   which 
  therefore 
  cannot 
  be 
  regarded 
  as 
  a 
  fair 
  sample 
  indicative 
  of 
  increased 
  

   metabolism. 
  The 
  objection 
  is 
  well 
  founded 
  as 
  regards 
  brief 
  sampling 
  during 
  

   the 
  period 
  of 
  establishment 
  of 
  augmented 
  breathing, 
  but 
  not 
  as 
  regards 
  brief 
  

   sampling 
  when 
  the 
  augmented 
  regime 
  has 
  become 
  established. 
  During 
  the 
  

   first 
  minute 
  or 
  two 
  of 
  increased 
  muscular 
  activity 
  the 
  increased 
  expiration 
  of 
  

   C0 
  2 
  is 
  partly 
  due 
  to 
  increased 
  pumping 
  action, 
  partly 
  to 
  increased 
  muscular 
  

   metabolism 
  ; 
  but 
  at 
  the 
  end 
  of 
  five 
  minutes 
  (or 
  less) 
  of 
  steady 
  work 
  a 
  steady 
  

   regime 
  of 
  CO2 
  output 
  is 
  established, 
  during 
  which 
  the 
  rate 
  of 
  output 
  is 
  

   unaffected, 
  or 
  inconsiderably 
  affected 
  by 
  variations 
  of 
  pump 
  effect. 
  A 
  person 
  

   breathing 
  at 
  rest 
  6 
  litres 
  per 
  minute 
  at 
  3 
  per 
  cent. 
  C0 
  2 
  , 
  i.e., 
  discharging 
  C0 
  2 
  

   at 
  the 
  rate 
  of 
  180 
  c.c. 
  per 
  minute 
  or 
  3 
  c.c. 
  per 
  second, 
  on 
  commencing 
  work 
  

   at 
  say 
  10 
  kgrm. 
  per 
  second 
  exhibits 
  at 
  once 
  an 
  increased 
  ventilation, 
  accom- 
  

   panied 
  by 
  a 
  rise 
  of 
  C0 
  2 
  percentage 
  and 
  a 
  total 
  increased 
  output 
  of 
  C0 
  2 
  , 
  which 
  

   during 
  the 
  first 
  minute 
  of 
  effort 
  is 
  certainly 
  the 
  resultant 
  of 
  two 
  factors, 
  

  

  