Leg cramps in swimming

A cramp is an involuntary, painful contraction of the muscles that does not relax like it should. Cramps that occur while swimming often originate in one of three places: your toes, the arch of the foot, or the calves, with the gastrocnemius and soleus muscles of the calves being more common. The pain has a quick onset that is usually severe enough to force swimmers stop because of the tenderness they experience in their leg. A calf cramp will usually disappear on its own, but tenderness can remain even after the cramp vanishes.

Read more »

Neck pain in swimming

One of the most common injuries in swimming is neck injury. Although swimming is a low impact exercise, it depends heavily on technique. That means that swimming badly will affect not only your speed and efficiency but will also lead to pain and stiffness. Neck pain and headache can be the result of several factors associated to your technique. Swimmers who suffer from neck injuries feel a constant, dull ache that may be present in the back of the head, top of forehead, behind the eye, in the temple region or less commonly, around the jaw or ear. Usually associated with neck pain, stiffness and difficulty turning the neck. Other symptoms may be present such as numbness, dizziness, nausea or light headedness.

Read more »

Hormonal responses during exercise

Hormones play important roles in providing energy to the muscles and nerves. They are also involved in replacing that energy. In addition, they play roles in repairing and building tissues. The following are some of the most important functions that hormones perform for athletes.

Endurance work increases the use of glucose by muscles. The following hormones facilitate the use and replacement of muscle glucose. An increase in secretion of the hormone glucagon facilitates the movement of glucose from the liver to the blood, which carries it to the working muscles. The hormones epinephrine (adrenaline) and norepinephrine are also secreted in additional amounts. They aid in the movement of liver glucose to the blood. The secretion of cortisol facilitates the conversion of liver glycogen to glucose. The increased secretion of the hormone insulin, is directly involved in transferring blood glucose into the working muscle fibers.

Read more »

Effects of training on blood pressure

Blood flowing through the vessels exerts pressure on the walls of these vessels. This pressure is called blood pressure and is measured by the number of millimeters that the blood causes a column of mercury to rise. We need two measurements of pressure to identify the force of the blood flow: the pressure when the heart beats and the pressure when it is resting between beats. The first is called systolic and second diastolic. Typical resting systolic and diastolic blood pressures are 120 and 80 mm Hg respectively.

Read more »

Effects of training on cardiac output

Cardiac output is defined as the amount of blood ejected from the heart during each minute. As with stroke volume; cardiac output is considered only the amount ejected from the left ventricle. The right ventricle will eject an equal amount of blood during the same time.

Read more »

Effects of training on heart rate

The number of times your heart contracts during each minute is your heart rate. Actually, both the right and left sides of the heart (the ventricles) contract simultaneously, but these two contractions count as one beat. The left ventricle of the heart fills with blood from the lungs during its rest period between beats. When the heart beats, it pumps that blood, out to the muscles. The right ventricle fills with blood returning from the muscles during the rest period and then pushes that blood out to the lungs.

Read more »

Effects of training on stroke volume

Stroke volume is termed the amount of blood that is pushed out of the ventricles of the heart with each beat.  A normal range of values at rest is between 60 and 130 ml per beat. These amounts can increase to between 150 and 180 ml per beat during exercise. These values refer only to the blood that is pumped out of the left ventricle. An equal amount of blood will simultaneously be pumped out of the right ventricle.

Read more »

Fast-twitch and slow-twitch muscle fibbers

There are, as you already know, two main categories of fibbers in the skeletal muscles of our bodies. The first type is known as slow twitch fibbers (or slow oxidative fibbers, or red fibbers, or Type I fibbers) and the second type is known as fast twitch fibbers (or white fibbers, or Type II fibbers). These two types distinguish one from another on how fast they can contract. Another important difference between them is in their capacity for endurance and power work.

Slow twitch fibbers have more endurance because they have a greater capacity for aerobic metabolism. They have more myoglobin (the substance that transports oxygen across the muscle cell), more aerobic enzymes that catalyze the release of energy during aerobic metabolism, and more mitochondria (the protein structures within muscle cells where aerobic metabolism occurs).

Read more »

Swimmer's ear

A lot of swimmers experience the discomfort the swimmer’s ear give throughout their swimming career. So, what is the swimmer’s ear and how can we prevent it?

Swimmer's ear is an infection in the outer ear canal, which runs from your eardrum to the outside of your head. It's often brought on by water that remains in your ear after swimming, creating a moist environment that aids bacterial growth.

Putting fingers, cotton swabs or other objects in your ears also can lead to swimmer's ear by damaging the thin layer of skin lining your ear canal.

Swimmer's ear is also known as acute external otitis or otitis externa. The most common cause of this infection is bacteria invading the skin inside your ear canal.

Read more »

Free radicals in exercise

Reactive oxygen species (ROS) are chemically reactive molecules containing oxygen. Examples include oxygen ions and peroxides. ROS form as a natural byproduct of the normal metabolism of oxygen and have important roles in cell signaling and homeostasis. However, during times of environmental stress (e.g., UV or heat exposure), ROS levels can increase dramatically. This may result in significant damage to cell structures. Cumulatively, this is known as oxidative stress. ROS are also generated by exogenous sources such asionizing radiation.

Read more »