Ready to jump-start your career?
Get your free evaluation kit today!
- Readiness quiz
- 5 Step plan to becoming certified
- How to enroll with ISSA
Caffeine is a crystal-like substance found in many beverages (coffee, tea, and cola), medications, and foods. Caffeine is quickly absorbed into the bloodstream and attains maximum values within 15 to 120 minutes of consumption. Through the blood, caffeine is spread to many tissues in the body, including the brain. Enzymes in the liver breakdown caffeine, leaving very little to be cleared in urine.
Caffeine has both central and peripheral effects in the body. In the central nervous system caffeine affects parts of the brain and the spinal cord, while in the periphery it affects organs and tissues. At low doses (2-10 mg/kg), it can cause increased alertness, less fatigue, reduced reaction time, increased ventilation, and poorer performance of some fine motor skills. At higher doses (>15 mg/kg), caffeine can cause nervousness, insomnia, headaches, and unsteadiness. Caffeine also has inconsistent effects on the cardiovascular system. Depending on where it acts in the body, caffeine can either raise or lower heart rate and cause blood vessels to constrict or dilate. Caffeine can cause a mild increase in urine output from the kidneys and dilation of the bronchi. Caffeine causes the release of epinephrine from the adrenal glands, which causes lipolysis (break down of fat) in muscle and adipose tissues. This increased mobilization of free fatty acids can lead to glycogen sparing early in the exercise period because the body uses relatively more free fatty acids for energy. Caffeine also directly acts on muscle cells by enhancing the release of calcium from the sarcoplasmic reticulum in muscles cells, which improves muscle contraction.
There are a variety of possible mechanisms by which caffeine is proposed to enhance athletic performance, many of which are mentioned above. The most researched and widely acknowledged mechanism is by glycogen sparing via increased fat utilization, thus allowing the athlete to exercise longer at a given submaximal intensity. Other mechanisms include increased catecholamine release, increased calcium release from muscle cells, and reduced perception of effort. On a cellular level, caffeine inhibits adenosine, causing increased urine excretion, stimulation of the central nervous system, increased lipolysis in fat cells (adipocytes) and increased gastric secretion. Increased lipolysis in fat cells occurs because caffeine reduces the inhibitory influence of adenosine on lipolysis, thus increasing lipolysis. These methods of enhanced athletic performance and other possible mechanisms are examined further throughout the course.
Features online enrollment, online exam and instant grading as well as automatic certificate generation upon completion of course.
Fitness is very important to me, and getting the certification makes that better.
You truly have wonderful programs that made me go to a whole new level in fitness and I am already applying my knowledge into new and exciting fitness ventures!
I've always been passionate about fitness, and ISSA gave me tools to build a knowledge base that I can continue to add to.
Ana Victoria Cate
I am so impressed by the level of professionalism and thoroughness that ISSA offers to trainees.
ISSA made it so easy for me to acquire my certificate as a Certified Personal Trainer, and I would also like to add that the course material was put together very well for me to understand.
The course itself was thorough and challenging, and it was great to have the flexibility to work it into my current schedule, as well as the convenience of being able to do everything online.
Kimberleigh Jade Larkan
I hold two certifications with the International Sports Sciences Association and I couldn't be more pleased with the support I've received.
I am really looking forward to helping people realize and reach their goals of becoming more healthy and physically fit, no matter their age.
The ISSA certified personal trainer program is the best experience of my life.
Thank you for the newest, modern, scientific information, which your course provides.
ISSA was a great school and has taught me many things about how to do this and the correct ways.
With ISSA guidance and textbooks, I have upgraded my knowledge to another level and I feel this by seeing big changes in my clients & myself!
Get your free evaluation kit today!
© 2019 ISSA. All rights reserved.Terms & Conditions