Analyse how the neural factors which regulate the cardiac and respiratory systems affect an endurance performer.[8 marks]

A01

Autonomic Nervous System

Proprioceptors

Baroreceptors

Thermoreceptors

sympathetic nervous system

Chemoreceptors

A02

  1. Increase firing rate / stimulate / SA node/ increasing heart rate / cardiac output
    
  1. Impulses / information sent to respiratory control centre medulla 
    

Via cardiac / accelerator nerve

  1. Increased stimulation / force of contraction of diaphragm  / external intercostals
    
  1. Impulses / information sent to cardiac control centre / medulla oblongata 
    
  1. Via phrenic nerve 
    
  1. Recruitment / stimulation of additional (inspiratory) muscles e.g. sternocleidomastoid / scalenes / pectoralis minor 
    
  1. Ribs move up and out further  / volume of thoracic cavity increases / pressure inside thoracic cavity decreases / more air enters / increases depth of breathing 
    
  1. Expiration becomes active / recruitment / stimulation expiratory muscles / internal intercostals / rectus abdominus / abdominals 
    
  1. Increases minute ventilation / tidal volume 
    

A03

  1. Increased tidal volume / minute ventilation means more oxygen inspired or breathed in 
    
  1. Hence increase in aerobic respiration 
    
  1. Increased heart rate / cardiac output means more oxygen / blood to working muscles 
    
  1. Performer be able to work for longer / at higher intensity / greater endurance capacity 
    
  1. Endurance performer relies on supply of oxygen to working muscles / aerobic respiration / aerobic system 
    
  1. Less build up of lactic acid e.g. run or cycle or swim faster 
    
  1. Delayed / increased lactate threshold or OBLA