Question

1. Mr. X is a long distance swimmer. He is regularly doing the training to maintain his swimming capacity.

Discuss about,

A. The muscle fiber type involved in this training and sports.

B. Discuss the muscular system adaptation with his swim training.

C. Add a note on energy systems that are involved in this sport.

Answer 1

Swimming is an aerobic exercise which require higher oxygen delivery to the muscles to meet the requirements.

1) There are two muscle fibre type - type 1 muscle fibres which are slow twitch fibres and type 2 muscle fibres which are fast twitch fibres.

Slow twitch fibres are more involved in activities like running, swimming, endurance training and cycling etc. These fibres have more blood supply and are thus fatigue resistance which is used for more prolonged activities.

Fast twitch fibres are more involved in sprinting, jumping and powerlifting etc. These fibres are used for short and high intensity activities.

2) Adaptations in muscles are -

a) they have higher content of mitochondria, thus more energy production required for muscle contraction.

b) they have more blood supply, thus delivery of more oxygen and nutrients take place.

c) they have higher levels of myoglobin which is the cheif protein responsible for oxygen delivery to muscle tissue.

d) they have lower levels of ATPase, thus degradation is less.

e) they have higher oxidative capacity.

f) they sustain long term contractions.

3) Energy system involved in this sport is an aerobic system where energy is produced in the form of ATPs from gycolysis, Krebs cycle and electron transport system.

In glycolysis, glucose is converted to pyruvate with the help of certain enzymes. Pyruvate produced from glycolysis is then converted into acetyl coenzyme A in the mitochondrial matrix and gets converted to carbon dioxide and water which marks the beginning of the Krebs cycle, which produce electrons and hydrogen ions. These electrons and hydrogen ions are used in electron transport chain located in the inner membrane of the mitochondria which produces ATP. This ATP produces is used as energy for activities.