Define the term overload as a principle of training. 

Using examples, discuss two ways overload could be applied to an endurance training programme.

Outline the functions of two components of blood.

Describe the cardiovascular adaptations resulting from endurance training.

Explain DOMS in relation to muscle contraction.

Compare and contrast slow and fast twitch muscle fibre types.

to train harder than you have previously✔

overload involves increasing intensity

eg when running increasing target heart rate from 70% maximum HR to 75% maximum HR✔

overload involves increasing duration

eg when running increasing training time from 20 minutes to 30 minutes✔

overload involves increasing frequency

eg increasing training frequency from three times a week to five times a week✔

Each application method must have an example.

Platelets/ thrombocytes:
assist in the process of repair following injury✔

allow the blood to clot✔

White blood cells / leucocytes:
involved in immune function / produce antibodies✔

protect the body from infection / foreign substances✔

Red blood cells / erythrocytes:
contain hemoglobin and transport oxygen✔

hemoglobin binds with oxygen forming oxyhemoglobin✔

hemoglobin increases the blood’s oxygen carrying capacity 65–75 times that above that normally dissolved in plasma✔

hemoglobin <contains a central iron ion which> can hold up to four oxygen atoms <per heme>✔

Plasma:
is the fluid component of the blood✔

assists in transport of substances such as food / waste products/ gases / hormones / antibodies✔

Award [2 max] per component.

Marks must come from 2 components only.

increased left ventricular volume / increased stroke volume so that it pumps more blood per beat✔

lower resting heart rate as the heart is stronger from training doesn’t need to work so hard at the same level✔

lower exercising heart rate when working at the same load as when untrained✔

increased arterio-venous oxygen difference so the muscles are able to extract a greater volume of oxygen from incoming blood✔

larger and more numerous mitochondria in trained skeletal muscle to produce more aerobic energy/ assist with recovery✔

increased level of aerobic system enzyme activity so it can create more ATP / energy✔

increased ability of the muscle to mobilize, deliver and oxidize lipid to prevent glycogen stores from running out✔

increased glycogen storage in the muscle due to increased muscle size / efficiency✔

increased capacity for glycogenolysis so you are able to turn more glycogen into glucose for ATP production✔

slight cardiac hypertrophy/increase in heart size due to training of the heart muscle✔

increase in blood ‹plasma› volume to support the bodies sweating needs and due to the increase in blood cells / maintain viscosity✔

increase in cardiac output as the heart is stronger/ larger so the heart can potentially pump more blood in a minute✔

increase in capillarization which will mean that greater volumes of blood / oxygen can be transported to muscle✔

increase in blood volume/RBC which means blood can carry more oxygen✔

Award [3 max] if adaptations are listed rather than described

DOMS occurs after exercise / up to 48 hrs post exercise <and can last three or four days>✔

eccentric and isometric actions tend to produce the greatest post exercise discomfort✔

concentric contraction does not cause DOMS to the degree that it is produced by eccentric contractions, due to greater microscopic tears in eccentric contractions✔

with DOMS comes a reduction in the force generating capacity of the affected muscles / negatively affects performance✔

DOMS can be produced by:
microscopic tears✔

osmotic pressure causing fluid retention in the surrounding tissues✔

muscle spasms✔

overstretching and tearing of muscle connective tissue✔

acute inflammation✔

alteration in the cells’ mechanism for calcium regulation✔

Award [2 max] for what DOMS can be produced by

Award [1] per row.

Many students struggled to articulate their definition of overload to clearly demonstrate their knowledge.

Many students struggled to refer to the principles of overload and discuss the ways in which it can be applied to endurance training.

Many students were able to achieve 2 marks, commonly referring to the red white blood cells and the platelets. However many students wrote about three components rather than a detailed answer for the two components.

This was a well answered question with many students identifying stroke volume increases and a reduction in resting heart rate. However many students struggled to achieve 5 marks because they simply listed the adaptations.

Few candidates gained more than two marks for this question. Many students referred to methods to prevent DOMS rather than explaining the causes and when DOMS occurs

Students were generally able to compare the difference between their main function. However many students were unable to identify and compare the main structural characteristics for both types of fibre.