Week 16: Cardio

What are some differences of the body's adaptation to the 2 types of training: cardio and strength training?

(P.19, Cardio)

Help mixed athletes incorporate their endurance training into their strength training program with minimal interference.

- Program in as little cardio as you need to achieve your desired energy deficit. Below 20 minutes each session is ideal. - Separate into many sessions if possible. - Separate the time between cardio and strength training as much as possible, ideally 6 hours. - Best to do cardio after than before strength training if possible. - Choose a concentric-only and low impact cardio modality that exercises relatively unimportant muscle groups. - Keep the intensity low enough that you can still breathe through your nose or hold a conversation. (P.35, 36, Cardio)

When to train cardio to prevent interference effect on strength training?

- Separate the cardio from your strength training by at least 6 hours. - You can do both cardio before or after strength training. + Your pre-workout cardio can serve as a warm-up. Don't overdo it. - If you can only do cardio once a day, It's best to perform the majority of the cardio post-workout. The interference effect is stronger for pre-workout than post-workout cardio, as pre-workout cardio interferes with the strength training session directly but strength training has minimal effect on the quality of the cardio. - If you have to do cardio earlier in the day but not later, separate your cardio and strength training as much as possible. (P.27, Cardio)

How much volume and duration of cardio should one do to minimize interference effect?

- The longer your cardio sessions, the worse the interference. - The interference effect for cardio sessions below 20 minutes is generally small. - If you have to perform a high volume of cardio because it's not feasible to decrease energy intake further, it's generally a good idea to spread it out over many sessions. As long as your cardio sessions are sufficiently short that they don't require much, if any, endurance adaptations to take place, you will minimize the interference effect. (P.26, Cardio)

Explain why cardio isn't necessary to get lean?

- There are many ways to burn fat and get lean. - Cardio's effect on fat loss is virtually entirely mediated by energy balance. - It doesn't matter how much fat you burn through cardio, what matters is energy balance (and nutrient partitioning) is affected over time. As long as you reduce your energy balance and go into energy deficit, you will lose fat and get leaner. - Cardio is not a very effective tool for getting lean because it doesn't build muscle and change your body composition. Strength training is a much better choice since it builds muscle, change body shape, and burn calories at the same time. (P.4 + P.6, Cardio + self-explanation)

What are some strategies to minimize interference effect?

1) Choose a concentric-only and low impact cardio modality that exercises relatively unimportant muscle groups. 2) Program in as little cardio as you need to achieve your desired energy deficit. 3) Keep the intensity low enough that you can still breathe through your nose or hold a conversation. 4) Perform the cardio workouts as far away from your strength training work as possible. If you combine the cardio and strength training in the same workout, split up the cardio work into a pre- and a post-workout session and take as much time as you want in between the sessions. (P.35, 36, Cardio)

What are some reasons women should not do HIIT?

1) The female nervous system is not as efficient as that of men. Men are more explosive than women: they can generate force quicker. The area in the brain that controls movement (the motor cortex) is in fact literally larger in men, even after correcting for height. 2) Women don't build as much muscle protein after high intensity sprints as men. 3) Women recover less well after HIIT type exercise like sprints. High volume sprint training can take over 72 hours to recover from in women. (P.32, Cardio)

What are the common problems that contest prep individuals usually have when trying to reach contest shape without cardio?

1. Hunger. 2. Nutrient deficiencies, at the micro- as well as the macro level. (P.25, Cardio)

How does AMPK activation in cardio training affect muscle synthesis?

AMPK activation can inhibit mTOR activation, thereby suppressing muscle protein synthesis and growth. (P.20, Cardio)

Constrained energy expenditure

Constrained energy expenditure: high levels of physical activity decrease other energy expenditure, most likely spontaneous physical activity (SPA)/non-exercise activity thermogenesis (NEAT). (P.17, Cardio) Activity thermogenesis seems to be constrained: high activity thermogenesis at one point reduces it later. Many individuals subconsciously reduce their energy expenditure, particularly their non-exercise physical activity level (NEAT), after (aerobic) exercise so that more exercise does not necessarily improve fat loss and sometimes doesn't even increase energy expenditure at all. (P.16, 17, Cardio) Explore why it is that exercise's impact on energy expenditure doesn't appear to be linearly "additive" - meaning that studies on energy expenditure suggest that increases in exercise, don't come with a comparable increase in total daily calories burned. (https://www.weightymatters.ca/2016/02/constrained-energy-expenditures-and-not.html)

Explain why more cardio does not always result in more energy expenditure.

Constrained energy expenditure: high levels of physical activity decrease other energy expenditure, most likely spontaneous physical activity (SPA)/non-exercise activity thermogenesis (NEAT). (P.17, Cardio) Activity thermogenesis seems to be constrained: high activity thermogenesis at one point reduces it later. Many individuals subconsciously reduce their energy expenditure, particularly their non-exercise physical activity level (NEAT), after (aerobic) exercise so that more exercise does not necessarily improve fat loss and sometimes doesn't even increase energy expenditure at all. (P.16, 17, Cardio) Low intensity exercise seems to be more strongly constrained, with the most consistent compensation seen for high general physical activity levels and less compensation after high-intensity exercise. (P.18, Cardio)

What is concurrent training effect?

Doing cardio alongside resistance training can decrease the positive effects of both but mainly those of strength training. Concurrent strength and endurance training can obstruct the development of power, strength and muscle growth compared to only performing strength training. (P.21, Cardio) Negative interaction between cardio and strength training is a result of trying to make a muscle adapt in two opposite directions. (P.22, Cardio)

How long does EPOC last and approximately how much calories does it really burn?

EPOC after even extreme cardio protocols typically lasts only 3 to 24 hours and comprises just 6 to 15% of the net total oxygen cost of the exercise session. That's a paltry number of calories. Even strength training sessions of 50 to 60 sets (!) don't cause more EPOC than 114 calories. (P.14, Cardio)

Excess post-exercise oxygen consumption (EPOC)

Excess post-exercise oxygen consumption (EPOC, informally called afterburn) is a measurably increased rate of oxygen intake following strenuous activity. (Wiki) In recovery, oxygen (EPOC) is used in the processes that restore the body to a resting state and adapt it to the exercise just performed. These include: hormone balancing, replenishment of fuel stores, cellular repair, innervation and anabolism. Post-exercise oxygen consumption replenishes the phosphagen system. New ATP is synthesized and some of this ATP donates phosphate groups to creatine until ATP and creatine levels are back to resting state levels again. Another use of EPOC is to fuel the body's increased metabolism from the increase in body temperature which occurs during exercise. (Wiki)

True or False? The main goal of cardio is to improve endurance.

False. The goal of cardio for fat loss is simply to increase energy expenditure, not to improve your endurance. (P.35, Cardio)

True or False? HIIT sprinting is better than steady-state cardio in both fat loss and muscle hypertrophy.

False. Both fat loss and muscle hypertrophy are similar between steady-state cardio and HIIT: most studies find that no muscle hypertrophy occurs beyond the novice level and minimal fat loss occurs. HIIT is just not that different from steady-state cardio for the body. (P.29, 30, Cardio)

True or False? Forms of cardio that involve eccentric muscle actions are better than those involve concentric muscle actions.

False. Forms of cardio that involve eccentric muscle actions result in more muscle damage than purely concentric cardio modalities. Since muscle damage can impair strength training performance and prolong recovery times, concentric-only forms of cardio are preferred. Examples include bicycling, stair walking, cross-training, rowing and skiing machines. (P.34, Cardio)

True or False? High intensity training has higher compensation from constrained energy expenditure than low intensity training.

False. Low intensity exercise seems to be more strongly constrained, with the most consistent compensation seen for high general physical activity levels and less compensation after high-intensity exercise. In fact, there is generally no NEAT compensation after pure strength training. Since cardio but not strength training suffers from constrained energy expenditure and strength training is more appetite suppressing, strength training is often a better choice than cardio for fat loss. (P.18, Cardio)

True or False? Research supports that the theory that our appetite increases after exercise.

False. Several reviews show that exercise, whether it's low or high intensity, does not increase our appetite. In fact, exercise, especially high intensity exercise, is significantly appetite suppressing and strength training is more appetite suppressing than endurance training [2]. Exercise puts your nervous system in fight-or-flight mode. If you're hungry during a workout, you're probably just not training hard. (P.16) If you're hungry after your workout, it's totally normal because it's because of your meal pattern habit. Also, on training day, people reach satiation faster than on a rest day. (Lecture)

True or False? HIIT combined with strength training provide both the benefits of endurance and strength.

False. Since HIIT causes strong endurance adaptations, it can cause a major interference effect with strength training, just like LISS. In fact, the higher the intensity of a given duration of concurrent endurance training on top of strength training, the worse the strength development. (P.30, Cardio)

True or False? HIIT resembles the training of a sprinter.

False. The idea that HIIT resembles the training of a sprinter is misguided. The training practices of elite level sprinters are comparable to those of other strength and power athletes like Olympic weightlifters and powerlifters: short, high intensity exercise followed by long rest periods. (P.29, Cardio)

True or False? Cold water immersion promotes fat loss effectively.

False. Cold water immersion can increase your appetite. This means swimming in cold water is generally not a good idea as cardio for fat loss. (P.35, Cardio)

What is fasted cardio?

Fasted cardio is cardiovascular training performed when the digestive system is no longer processing food, which can happen four to six hours after eating or in the morning after you've woken up. (Google)

Explain why a given energy expenditure of cardio results in the same fat loss regardless of whether it's performed fasted or fed or in the 'fat burning zone' or below it.

Given the same energy deficit, fat loss is the same regardless of whether you do your cardio in the fasted or fed state. It doesn't matter if you burn more fat during the cardio session. Regardless of which substrate you burn when, in the end the total energy balance still governs total body energy change. (P.7, Cardio)

Explain why doing your cardio fasted doesn't help and may even be detrimental?

Given the same energy deficit, fat loss is the same regardless of whether you do your cardio in the fasted or fed state. It doesn't matter if you burn more fat during the cardio session. Regardless of which substrate you burn when, in the end the total energy balance still governs total body energy change. (P.7, Cardio) Endurance training can interfere with strength training by promoting protein catabolism, thus losing muscle. (P.21, Cardio) Fasted cardio can also be detrimental by making you lose muscle mass. First of all, cortisol is at its highest in the morning (the cortisol spike is what allows you to have energy when you wake-up). If you don't eat, it will stay elevated and even increase. And if you couple it with cardio, which also tends to jack up cortisol output, you'll end up with a sky-high cortisol level, which is one of the best ways to lose muscle. Not only that, if it gets high enough you'll actually have a hard time bringing it down during the day (especially when in a caloric deficit). You end up spending the whole day in a muscle-wasting state! (https://www.t-nation.com/training/fasted-cardio-eats-muscle)

Pros and Cons of HIIT and LISS?

HIIT: save time, more interference effect to strength training than LISS. LISS: less interference effect to strength training, more energy expenditure potential. (P.31, Cardio)

Actual energy expenditure of a BodyPump class?

People have been found to overestimate the energy expenditure of a BodyPump class by 67%. The actual energy expenditure was only 5 kcal/min. (P.10, Cardio)

How to estimate the energy expenditure of various cardio workouts.

See table P.11-P13 Energy expenditure during a cardio session typically ranges from a few hundred calories up to 600 kcal per hour. (P.8, Cardio)

Help someone decide whether they should be doing cardio and, if so, how exactly?

Since for fat loss cardio training is no more effective than eating equivalently fewer calories and cardio also has the cost of interfering with your strength training, cardio is normally best avoided in optimized training programs. However, cardio is sometimes a necessary evil, specifically for physique contest preparation. 2 problems arise: 1. Hunger, which can be managed. 2. Nutrient deficiencies, at the micro- as well as the macro level. Micro can be managed. But on Macro level, Protein intake cannot be compromised on under any circumstance. Carbohydrate intake often can, but ketosis may not be desirable. Fat intake can be compromised on in the short-term, but over the course of weeks or months this will most likely impair the competitor's results and health. Women anecdotally seem to lose their menstrual cycle earlier on bro diets with very little fat. Since most people will be left with at least some issues at very low energy intakes, a reasonable guideline is to not decrease energy intake below 1200 calories on training days for women or 1800 kcal for men unless you absolutely need to. Beyond this point, the costs of cardio may be less than the costs of further decreases in energy intake. How: - Program in as little cardio as you need to achieve your desired energy deficit. Below 20 minutes each session is ideal. - Separate into many sessions if possible. - Separate the time between cardio and strength training as much as possible, ideally 6 hours. - Best to do cardio after than before strength training if possible. - Choose a concentric-only and low impact cardio modality that exercises relatively unimportant muscle groups. - Keep the intensity low enough that you can still breathe through your nose or hold a conversation. (P.35, 36, Cardio) Note: So if you have certain muscle groups that don't need to become bigger, it's best to choose a form of cardio that relies primarily on these muscle groups. - Women: HIIT is often a particularly bad idea for women. While women typically have great endurance, and recover faster than men, the female nervous system is not as efficient as that of men. - Men's Physique: Competitors wear board shorts on stage, so they may be able to compromise on their thigh and glute development and perform bike ergometer cardio. - Bikini competitors generally don't need to maximize muscle growth in their backs or arms, so upper body rowing can be a suitable form of cardio.

Explain why adding 20 minutes of bicycling to someone's strength training workouts may increase their quadriceps muscle growth if they're untrained yet decrease it if they're highly trained.

The adaptation process to any kind of training in beginners is still very general. So in untrained individuals, adding endurance training to a low volume of strength training can add to the stimulus for muscle growth. In untrained individuals, strength and endurance training activate very similar anabolic gene pathways. When we look at highly-trained endurance or strength trainees, we can see endurance vs. strength training activate much more clearly divergent cellular signaling pathway. (P.23, Cardio)

What is the fat burning zone and why is it a myth?

The fat-burning zone is a concept that the body burns a greater amount of fat at lower-intensity aerobic exercise than it does at higher intensities. Actually, the body burns a greater percentage of fat at lower intensities than at higher intensities. At lower intensities, the body may burn 50 percent of the calories from fat, while at higher intensities it may only burn 35 percent. But at higher intensities you burn way more total calories—and more fat calories overall—than you do at lower intensities. (Google) For the sake of fat loss it doesn't matter how much fat you burn acutely but rather how your energy balance (and nutrient partitioning) is affected over time. You can do all the cardio in the world, but if you don't sufficiently reduce your energy balance, physics dictate that you won't lose net body fat mass. So given the same energy expenditure, high and low intensity cardio result in the same fat loss. (P.6, Cardio)

Rate of Perceived Exertion (RPE)

The subjective perception of effort during exercise that can be used to monitor exercise intensity. (Quizlet)

True or False? Zumba classes get much closer to heavy strength training in terms of energy expenditure.

True. (P.10, Cardio)

True or False? It doesn't make a difference if you reduce your energy balance by doing cardio or by eating less.

True. Cardio's effect on fat loss is virtually entirely mediated by energy balance. It doesn't matter if you reduce your energy balance by doing cardio or by eating less: given the same energy balance, weight and fat loss are the same (P.4, Cardio)

True or False? Constrained Energy Expenditure doesn't apply much to strength training.

True. Constrained Energy Expenditure mostly apply to low-intensity exercise. (8:10, Lecture, Cardio)

True or False? Over long term, instead of doing HIIT, people should increase their strength training frequency.

True. People that prefer HIIT over steady-state cardio are often better off increasing their strength training frequency (see the course topic on training frequency). (P.32, Cardio)

True or False? Any exercise, even endurance training can promote muscle growth in completely untrained individuals, regardless of whether you do strength training at the same time or not.

True. The adaptation process to any kind of training in beginners is still very general. So in untrained individuals, adding endurance training to a low volume of strength training can add to the stimulus for muscle growth. In untrained individuals, strength and endurance training activate very similar anabolic gene pathways, but the adaptation process starts differentiating rapidly within the first 8- 10 weeks [2, 3] and that's when concurrent training starts blunting mTOR signaling. When we look at highly-trained endurance or strength trainees, we can see endurance vs. strength training activate much more clearly divergent cellular signaling pathways [2]. (P.23, Cardio)