Cardio

Learning and Review: Cardiovascular Exercise

Cardiovascular Exercise: Cardio: Aerobic exercise which intends to improve the oxygen system.  The heart rate is maintained at at least 50% of its maximum level.

Some science facts:
Ways of burning glucose/sugar: 1. Aerobic (with oxygen) or 2. Anaerobic (without oxygen. leads to lactate) 

ATP: energy currency of muscle cells. 
It is produced in the mitochondria in cells ("the energy factory" of a cell). Mitochondria produce energy (ATP). Mitochondria is able to increase in size and number. Increased size and number leads to an increased availability of energy. Break down carbohydrate and fat for fuel.

Calorie = unit of energy.

Energy: 

Sources at rest: Fats 80–90%; carbohydrates 5–18% and protein 2–5%

Sources during exercise: muscle carbohydrate stores (glycogen), blood sugar, blood fatty acids, and intramuscular triacylglycerols (fat that is stored in muscle and fat tissues).

Factors: intensity and duration of exercise, the initial muscle glycogen levels, and supplementation with carbohydrates during exercise.

Typically: 
Light-Moderate use mainly glycogen, glucose and fat. 
Endurance sport relies on mainly Glycogen. 

Muscle growth (hypertrophy) occurs by satellite cells, providing there is sufficient amino acids available i.e. a positive nitrogen status by ingesting more protein than is lost. (amino acids --> protein synthesis: MUSCLE IS A PROTEIN). 

Steady State Cardio vs HIIT

Steady state/LISS:

->30minutes 

-burn calories and increase fitness/endurance. 

-low- moderate: able to hold a conversation

-e.g. walking on treadmill, riding bike

-heart rate at >65% of its maximum ability. 

-Aerobic system. 

- The muscle fibres used are Slow Twitch: Contract slowly, but keep going for a long time. 

Slow twitch fibres are red; they rely on a rich supply of oxygenated blood as they use oxygen to produce energy for muscle contraction. (AEROBIC)

Cardiac output = Heart Rate Stroke Volume

i.e. The volume of blood pumped from the heart in one minute is the sum of the number of beats of the heart per minute and the volume of blood pumped by the heart in each contraction. This enables the oxygen demands of the exercising muscles to be met.

Aerobic fitness is largely determined by Stroke Volume (which in itself is largely determined by Pre-load- i.e. how much blood is inside the ventricle). 

HIIT
-spike your heart rate (>85%)
-aim of burning fat and increasing your fitness. 
-Short sprint intervals are coupled with low-moderate intensity. (bursts of speed at your full maximum)
-Examples include alternating a sprint (for, say 15 seconds), with a slower paced walk/jog (for, say 60 seconds), doing burpees, weight lifting. 
-Anaerobic system: generates Lactate.  

- The muscle fibres used are Fast Twitch: 
Contract quickly, but rapidly get tired

Fast twitch fibres don't use oxygen to make energy, so they don't need such a rich blood supply (typically lighter in colour) (ANAEROBIC)

Calories burnt

• 15minutes of steady state cardio reads more kcal burnt than if you had done 15minutes of HIIT (alternating 1m sprint with 1m walk, for example). 
• LISS: burn calories at precise moment
• However, HIIT training is known for its 'afterburn' i.e calories are burned not only at the moment that you are exercising, but also for hours after: 24 hours. This is due to an elevated EPOC, which is the oxygen consumption - and thus caloric expenditure- after an exercise session. This has been depicted in LaForgia, Withers& Gore study whereby EPOC has a greater increase in HIIT than in steady state cardio.

Problem with endurance training:

-Body adapts to physiological stresses: Typically, 30-60minutes 3-7x week of endurance training leads to long term adaptions such as increased thickness of heart muscle, to become more effective and efficient as a pump. 

Improved cardiovascular function leads to an increased VO2 Max. 

VO2 MAX: ability to consume, distribute and use oxygen as a means to provided energy. It is a predictor of exercise performance. Increased VO2 max leads to improved exercise performance.

Having to challenge the body after it adapts (as aerobic fitness increases)

• increasing the duration of the exercise: PROBLEM: Now if you are already doing a 45 minute run, and you have to increase it to 60minutes --> boring or time consuming. 

A study by Wilson et al  showed a temporary boost in weight loss with steady state cardio, that was short-lived once the metabolism adjusted. The study also showed there was more muscle loss in steady state cardio than in HIIT. 

Another 8week study by Daussin et al showed HIIT produced physiological gains, such as an increase in VO2 Max (15% in HIIT, 9% in steady state cardio), and an overall increase in performance and health. This is supported by Helgerud et al. 

How to changing your metabolism

1. increase muscle muss
2. Increase muscle’s oxidative capacity (mitochondria: number and activity: produce ATP and burn fats)

Gibala et al: 

HIIT: increase in the number and size of mitochondria 

Burgomaster et al, MacDougall et al:

increase in oxidative enzymes within the mitochondria

In terms of Fat burning, 

Perry et al:

-increase in fat burning with HIIT in 6 weeks 

Talanian et al:

-also presented this finding but in a 2 week study. 

Horowitz & Klein:

-ncrease in fat burning with steady state cardiovascular exercise also. 

Remember: If you see a form of exercise as a chore, something you really hate the idea of doing, guess what... YOU WONT BE DOING IT FOR LONG.. you will resent it, and resent your workouts, and mentally that will hinder your progress. Do what you love and love what you do. Do what gets you pumped and rearing to go, and if that is a 30-45minute run then DO THAT and ENJOY IT and F anyone who judges. Whatever works for you will WORK and lead to results. LIFESTYLE CHANGE- not short term fixes.

Cardio: more fat burnt as fuel but this is short term. I.e. short term studies show that steady state cardio is best for fat burning.
HIIT: Due to the changes in the Mitochondria, HIIT is ultimately the best. i.e. Long term studies show HIIT has the best change in overall body fat composition.

Initiating a Change

When it comes to living a fitness-lifestyle, one quote that really does prove to be true is "if you fail to plan, you plan to fail". I found this relevant to my nutrition and diet, as well as my gym workouts. There was a time i used to go in to the gym and leave it up to how i felt once i was inside, and whether it was a "treadmill" day, or a "crosstrainer" day, or a "do weights/abs at the end" day etc. I knew this wasn't going to really get me the goals i wanted, but i didn't really know how to change my mindset. Once you get into a routine of thinking or acting a certain way, it becomes difficult to change it. Then i realised:

Well, ain't that the truth. So i was going to have to change something. And the way i initiated that change was to get involved in some gym classes. I used to think gym classes were nonsense. How can a class really help you when its not individualised, tailored to your own personal fitness, goals, age, weight etc. And i did get some stick from it, about it being the lazy option, too generalised ETC. But it helped. It challenged me because the trainer taking the class would push me, and i was able to challenge my comfort zone. Now i used to go extremely "hard" at the gym before, make no assumption that i was a weakling, slowly jogging for 2 minutes then stopping. NO. I was always dripping with sweat by the end of my workout, i would make sure i pushed myself to the point of fatigue, often did HIIT sprints, and was commended by guys at how "hard i go", unlike a lot of the girls at my gym who looked beautiful at the beginning and beautiful by the end. Nope, i was a sweaty pig. But going to the classes made me alter my mindset and that was the beginning of something great. I started seeing exercise as a way of sculpting my body as opposed to "burning off the calories i had eaten". I started to change the way i reached fatigue, say by going to spinning and sprinting right at the beginning of my exercise for longer or with more resistance than if i had been doing it myself. I stopped listening to my own voice and started pushing my body. 

I also started to get introduced to implementing weights into my workout, and centre-ing a workout around weights. I knew that women were being encouraged to get off the treadmill and "lift heavy", but that was so difficult for me to actually do when my gym was full of young, ripped 20 year olds leaving no space for anyone on the weights section. It was easier to "push myself hard'" on the treadmill, then venture over and "go lift". Not only that, but i didn't know what the hell i would be doing. What weight would i use? What if i used bad form? A rep? A set? It was all really confusing and overwhelming. But the classes helped me break that mentality and start to learn the concept behind weights, and the names for certain exercises, including the form, what was an okay weight for me etc. I built the courage. I knew, however, that in order to get the real results i was after that i couldn't just depend on classes. I had to take what i had learnt from doing the classes and implement it into the gym. I started becoming "used to" the classes, and felt it was actually going to hold me back. Body Pump, in particular, is one that comes to mind: it helped me in so many ways to get acquainted with weights, but the very high rep range meant that i wasn't using heavy or even slightly-heavy weights because we were doing 3293481239 reps of each exercise. NOW there is a lot of debate regarded high rep:lower weight vs low rep:heavy weight vs very low rep:extremely heavy weight, but body pump uses A LOT more reps. An entire song worth of reps with sometimes no break. It also means that you cheat on your form, because by the 2394234th rep, your muscle does fatigue and because you have to keep going (in synchrony with the rest of the class), you end up losing the true form of the exercise that is imperative to working the muscle. NOW I AM NOT SLAYING BODY PUMP. it was FANTASTIC. and without it i would NOT have ever got the stamina, knowledge or courage to step into the weight section of the gym. I would still be on that treadmill, sweating my calories away but not reaching my goals. 

This is why i repeatedly use the term "Journey", when discussing my experience with fitness and nutrition. You cannot begin as an expert. It takes a lot of trial and a hell of a lot of errors. And i sure am still learning, making trials and errors (on a weekly basis). You will wish you had known what you know now months before, but it takes failure to reach success. You will wish you had started sooner than you had. One thing is for sure, you can't just read about it and learn, you have to go out there and experience this for yourself. Classes worked for me, but they may not necessarily for you AND THAT'S OKAY. You just have to find what does. And you will.

This is a photo i took this morning of my progress:

September 13th