The nervous and endocrine system

1. Lloyd Dean
The Nervous and Endocrine System

2. Aims
By the end of the lesson you should be able to:
Explain the role of the nervous system
Describe the two parts of the nervous system
State how regular activity can enhance neuromuscular connections
and improve motor fitness
List the endocrine glands and hormones involved in exercise
preparation and performance

4. The Role of The Nervous System
Question:
What happens when someone shines a bright light in your eye?
What do you do if you place your hand on something hot, for example an hob on an oven?
This is the role of the nervous system; your brain registers the event after it has
happened. When a doctor taps your knee they are testing the involuntary
response of the brain!
Actions throughout the body need to be coordinated in an effective and
productive way
The nervous system communicates with the body to help this
The nervous system and endocrine systems are the communication super
powers!

5. The Nervous System
Nervous system can be broken down into
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
Central Nervous System (CNS)
The CNS is the main “switchboard” of the communication
Brain and spinal cord
Controls the movements of the body by working with the PNS
Interprets stimuli

7. The Nervous System
Peripheral Nervous System (PNS)
Consists of all the other neurones outside of the CNS
Communicates and works with, the CNS
Receives the stimuli via senses (Touching hot iron)
Further subdivided into:
Sensory Neurones – Transmit impulses from a receptor to CNS
Motor Neurones – Transmit impulses from CNS to effectors (Muscle or
Gland). Further subdivided into:
Somatic Nervous System – Involves voluntary movement of skeletal muscles
Autonomic Nervous System – Carries nerve impulses from CNS to organs.

8. Autonomic Nervous System
This means “self adjusting” and is involuntary
Is further broken down into:
Sympathetic Nervous System – Arouses the body “Fight or
Flight” (Increase HR, vasodilatation)
Parasympathetic Nervous System – Relaxes the body
(Decrease HR, vasoconstriction)

13. What Does Pinky Keep On Saying?!

15. Enhancing Neuromuscular
Connections
The neuromuscular junction (NMJ) is the communication point
between the brain and the muscles
Anaerobic training, usually 7 weeks required, can increase the
communication and improve motor fitness - HOW?!
Increasing the overall area of NMJ
More dispersed synapse
Increase of acetylcholine receptors

16. Improving Motor Fitness
Increasing the overall area of NMJ
When the overall area of the NMJ increase more muscle fibres can become
recruited, thus increasing strength over a period of time
Training in first 4 weeks
More dispersed synapse
A synapses if where two neurones meet
They control the messages sent from the nervous system
They allow one neurone to stimulate several other neurones
An increase can result in more activation of the muscle
Increase of acetylcholine receptors
Used for skeletal muscle contraction
More of this hormone results in more recruitment of muscle fibres

17. Endocrine Glands and Hormones
Understanding endocrine glands and hormones is vital when planning
training
Different types of training methods can impact hormonal release and
adaptations
Hormones are chemical messengers that are released into the body by
endocrine glands
These are released via neural stimulation
Hormones will put body in a anabolic (insulin, testosterone, hgh) or a
catabolic state (cortisol, progesterone)

19. Etherton, (2006)

20. Endocrine System
Pancreas Adrenal Glands
Large, pale coloured gland found behind stomach
Produces insulin and glucagon
Controls blood glucose levels
Failure to regulate insulin is know as “diabetes
mellitus”
Mellitus is Latin for honey
Blood glucose mechanisms cannot work properly
Type 1 – Unable to produce insulin
Type 2 – Cannot produce sufficient insulin
Sits at the top of the kidneys
Produce adrenaline which is
used for fight or flight
response
Adrenaline increases the
sensitivity of the nervous
system

22. How Can Athletes Manipulate The Endocrine System
With Resistance Training (Baechle & Earle, 2008)
General Concepts
The more muscle fibres recruited for an exercise, the greater the extent of potential remodelling
process in the whole muscle
To Increase Growth Hormone Levels
Use workouts with higher lactate concentrations
High intensity (10RM with 3 sets of each exercise and short rest periods)
Supplement diet with carbohydrate and protein before and after workloads
To Increase Testosterone Concentrations
Large muscle group exercises (Deadlift, Power Clean, Squats)
Heavy Resistance (85 – 95% of 1RM)
Short rest intervals (30 – 60 seconds)
To Optimise Responses To Adrenal Hormones
Use high volume, large muscle groups and short rest periods but vary the training protocol and the
rest period length and volume to allow the adrenal gland to engage in recovery processes and to
prevent a catabolic effect. This will ensure that the stress of training will not result in overtraining or
overuse injuries.

23. Aims
You should now be able to:
Explain the role of the nervous system
Describe the two parts of the nervous system
State how regular activity can enhance neuromuscular connections
and improve motor fitness
List the endocrine glands and hormones involved in exercise
preparation and performance