Fitness 101: Improve endurance and fat loss – Andrew Huberman ft. Andy Galpin podcast notes

In this episode, you will discover the definition and mechanisms that are involved in endurance and fat loss. Andy answers the question of how fat loses the body and defines the different energy systems that exist in the body and at the end a planning suggestion from Andy to run your first marathon.

 

What is endurance?

 

• • Endurance is the ability to perform work repeatedly while maintaining proper mechanics

• • Maintaining proper mechanics depends on
    

     

    • • Breathing properly
    • • Proper technique (posture, movement positions)

• • Different types of endurance:
    
    

     

    • • Muscular Endurance: The capacity to repeat small efforts in a muscle group without feeling excessive strain or fatigue, such as climbing stairs without experiencing burning sensations.
    • • Maximum Anaerobic Capacity: The ability to perform high-intensity work for a short duration, typically ranging from 20 to 80 seconds, such as paddling vigorously while surfing or cycling uphill.
    • • Maximum Aerobic Capacity: The capability to repeat a high-intensity effort for a longer period, usually lasting between five to 15 minutes, like running a mile or engaging in similar intervals.

 

• • True endurance goes beyond merely being able to perform physical activities; it also involves feeling good and energized afterwards.

• • Endurance depends on two factors: 1- Fatigue management and 2- Fueling

• • You should be training the full endurance spectrum: from steady state to high intensity.

 

• • Cardiac metrics that will improve with endurance training

 

• • Cardiac output: the amount of blood volume coming out per heart pump

• • Resting heart rate (HR when you’re doing nothing) goes down

• • Improved efficiency: means you can do more work at the same heart rate.

 

• • Maximum heart rate is not a reliable indicator of fitness, and increasing it is not necessarily beneficial. It is suggested to engage in training that raises heart rate towards the maximum level while focusing on overall cardiovascular fitness.
    
    

EXERCISE SNACKS CONCEPT

 

• • Every so often throughout the day if you’re feeling sluggish, move your body for max output for a short period of time. It can be doing jumping jacks, burpees or running up and down the stairs. 

• • In a study, participants did a 20-second bout of all-out work every hour three times a week for 6 weeks and saw a massive improvement in their VO2 max as well as a number of cognitive benefits, and work productivity. 

• • And if you had a high glycemic index meal, doing these short bouts of exercise will help mitigate the glucose spikes and crashes. 

FAT LOSS:

How fat leaves the body?

 

• • Fat is broken down into carbon molecules, and the body needs to get rid of these carbon molecules. When we breathe in oxygen, we exhale carbon dioxide (CO2), and this is how the carbon leaves our body.
    
    

 

• • Carbohydrates and fats are made up of carbon chains, and metabolism is essentially the process of breaking these carbon bonds to release energy. The energy is used to create ATP, which is the main source of energy for living beings.
    
    

 

• • Carbon life cycle:  plants take in CO2 and release O2 through photosynthesis, while humans and animals do the opposite. Humans obtain carbon by ingesting carbohydrates, fats, and other carbon-containing substances. The carbon is stored in various forms like glycogen in muscles and liver, and fat in adipose tissue. When the body needs to lose weight or reduce stored carbon, it breaks down these molecules and releases the carbon, which is then expelled through respiration.
    
    

 

• • There are no free passes in physiology and that fat loss ultimately comes down to ingesting less carbon or expelling more carbon. The concept of “calories in, calories out” is reframed as “carbon in and carbon out.” It is explained that the type of macronutrients (fats or carbohydrates) doesn’t matter as much as the total intake of carbon.
    
    

 

• • Anything you do that increases respiration rate will result in fat oxidation such as steady-state exercise, weightlifting, or intervals … 
    
    

Energy utilization & Fat loss

 

• • Crossover concept: The more intense the exercise is the more you tap into your carbohydrate storage more than your fat storage.
    

     

    • • At lower-intensity exercises, the highest percentage of fuel is coming from fat. But the total fuel expenditure is low.
    • • The higher the intensity gets, the more the percentage shifts towards burning more carbohydrates than fat.
        
        

• • Andy debunks the idea that exercising in a fasted state enhances fat loss. They explain that the body always has sufficient fuel reserves, such as muscle glycogen, liver glycogen, and blood glucose, to support most types of exercise. The percentage of fuel derived from fat may increase during lower-intensity exercise, but the overall energy expenditure remains low. Therefore, the notion of exercising in a fasted state for increased fat burning is not supported by energetic principles.
    
    

• • Maximizing fat burning during exercise does not necessarily lead to optimal fat loss. The percentage of fat burned during exercise does not equate to overall fat loss, as total energy expenditure and metabolic processes are more complex than a simple percentage calculation.
    
    

 

• • Replenishing muscle glycogen and losing fat: in a hypocaloric state, ingested carbohydrates bias toward glycogen storage to replenish muscle glycogen, while fat is utilized as fuel for activity, resulting in a shift in the respiratory quotient. The energy expenditure from fat increases and the energy from carbohydrates is stored in the muscles.
    
    

Metabolic flexibility

 

• • Carbs and fats are complimentary and you need to be able to tap into both sorts of fuel depending on the activity. This is referred to as “metabolic flexibility”

 

• • You may need to improve your metabolic flexibility If you cannot do a normal workout (15min) fasted or crash with a reasonable amount of carbs

• • Your blood glucose level should be at 85 or lower. There are some papers that show every single point increase above 85 increases your likelihood of developing type two diabetes by about 6%.

Muscle mass and BMR

 

• • Muscle is metabolically demanding and can increase basal metabolic rate. However, the impact of muscle on calorie burning is not as significant as commonly believed.

 

• • It’s commonly believed that you use around 50 calories per day per pound of muscle, but this number is exaggerated. More recent estimates suggest a lower value, around 6 to 10 calories per day per pound of muscle. 

 

• • The consequences of inadequate muscle mass can make fat loss more challenging.

 

• • Worrying about the exact number of calories burned from added muscle may not be as crucial as maintaining a calorie deficit and paying attention to overall dietary habits.

 

• • Caffeine use for fasted training may indicate inefficient fuel utilization

• • Caffeine can be used as an ergogenic aid for performance enhancement

• • Eating carbs late at night does not increase fat; this is an outdated belief

• • Proper meal timing and nutrient combinations stabilize blood glucose levels

• • Consuming fat before exercise signals a preference for fat utilization but may slightly hinder
    performance and consuming carbs before exercise biases the body towards carbohydrate utilization

• • Managing caloric intake and training at high intensity is important for energy management

The misconception around lactate

 

• • Lactate is not a limiting factor or a cause of fatigue; it is a highly effective and preferred fuel source. Lactate is produced to buffer the negative effects of ATP hydrolysis during exercise. Lactate can be used as fuel by neighbouring muscle fibres, converted into glucose or glycogen, or transported to the liver for gluconeogenesis.

 

• • The association between lactate and fatigue is based on correlation, not causation.

• • Clearing or reducing lactate in the muscle after exercise is unnecessary for performance.

 

• • High lactate levels indicate the presence of other byproducts from intense exercise. It has been associated with improved cognitive function and memory.

How energy used in long-duration exercise

 

• • Endurance exercise relies on the utilization of carbohydrates as a fuel source.

• • The initial phase of exercise involves anaerobic glycolysis, which provides a limited amount of energy.

• • After the initial phase, aerobic glycolysis kicks in and can sustain exercise for a longer duration, ranging from 90 seconds to 20-30 minutes or more.

• • Highly competitive marathon runners primarily rely on carbohydrates as their fuel source, with fat metabolism being too slow for sustained high-intensity exercise. This is why they may use specific strategies for fueling during long races, such as ingesting carbohydrates or utilizing fat as a fuel source.

• • Average individuals engaging in moderate-duration cardio exercises (e.g., 1-1.5 hours) are not limited by carbohydrate stores but may face other limiting factors.

• • Ingesting too many fast carbohydrates before exercise can lead to a crash in blood sugar due to the insulin-glucose double whammy.

• • It is advisable to practice the same nutrition and fueling strategies during training as planned for races to avoid unexpected reactions or outcomes.

• • Endurance exercise is ultimately about managing waste production, fatigue resistance, and energy production through the utilization of ATP and carbon metabolism.

Protein & Fat as energy source

FAT:

 

• • Fat is primarily used as a fuel source during aerobic exercise, and the majority of fat comes from systemic stores rather than muscle.

The process:

 

• • Fat is obtained through lipolysis, where stored fat is broken down into glycerol and fatty acids, which are then transported to the muscle.

• • Fatty acids longer than eight carbons require a special transporter to enter the muscle, while shorter-chain triglycerides can be used immediately as an energy source.

• • Metabolizing fatty acids involves beta-oxidation, where two carbons are cut off at a time to produce acetyl-CoA for the Krebs cycle.

• • The final endpoint of both carbohydrate and fat metabolism is water, ATP, and CO2.

• • When it comes to maximizing fat loss, the type of exercise (steady state or high intensity) doesn’t matter significantly; choose what is challenging and enjoyable for you.

• • The relationship between exercise type/intensity and hunger stimulus is not fully understood, but there might be individual differences in appetite response.

• • Overall, any form of exercise that creates a caloric deficit can lead to fat loss, regardless of whether it predominantly uses carbohydrates, fats, or proteins as fuel sources.

Protein

 

• • Protein represents a small percentage (10%) of energy output and becomes a more significant fuel source when muscle and liver glycogen levels are low.

• • Protein is not an efficient fuel source for the body.

• • The body stores carbohydrates (glycogen) and fat in larger quantities and can provide long-lasting energy, whereas protein stores are limited.

Impact of low carb diets

 

• • Low-carbohydrate or zero-carbohydrate diets can lead to adaptations in the body to generate glucose from alternative sources. These adaptations bias the body towards fat adaptation but can result in slower performance, especially during anaerobic activities.

• • Low-carbohydrate diets can be effective for weight management and energy stabilization in individuals with low physical activity levels.

• • Personal preferences and other factors should be considered when crafting a nutrition strategy for performance, aesthetics, and health.

Muscular endurance

 

• • Muscular endurance is the ability of a muscle to sustain repeated contractions over a prolonged period. It is a local muscle issue, not a cardiovascular or systemic issue.

 

• • Muscular endurance is measured by the number of repetitions or duration of an activity, such as push-ups, sit-ups, or hanging on a bar.

 

• • The limiting factors in muscular endurance are high pH rise (acid buildup) and difficulty clearing waste from the muscle tissue.

 

• • Capillarisation (creation of blood vessels) is important for muscular endurance as it improves blood flow, nutrient exchange, and waste product removal.

 

• • Training for muscular endurance requires high-precision exercise selection, focusing on specific muscle groups and movements. Exercise order is flexible, but larger muscle groups should be prioritized to minimize systemic fatigue.

 

• • The load for muscular endurance should be around the target repetition range, not too heavy or too light.

 

• • Training for muscular endurance should be distinguished from training for hypertrophy (muscle growth), as they have different rep ranges and goals.

 

• • For a typical person who wants to be all-around fit, incorporating muscular endurance training after other workouts can be a reasonable protocol. It may include exercises like planks, wall sits, and push-ups to maximum duration/repetitions multiple times a week.

Anaerobic capacity

 

• • Anaerobic capacity refers to the total amount of work that can be done in seconds to a few minutes.

• • The primary limitations of anaerobic capacity are muscle glycogen depletion and the buildup of acid byproducts, leading to oxygen transportation problems.

• • Increases in anaerobic capacity are beneficial even for endurance athletes or recreational exercisers as it improves overall cardiovascular fitness.

• • Andy suggests a protocol called “the sugar cane” for a workout challenge. It involves completing three rounds of exercise with two minutes of rest in between.  (6min in total)
    

     

    • • In round one, you aim to cover as much distance as possible in a specific time frame (e.g., two minutes).
    • • In round two, you try to cover the same distance as in round one, regardless of how long it takes.
    • • In round three, you aim to cover a greater distance in the same time frame as round two.

• • The protocol allows for progression by increasing the number of rounds or improving the work output each week. You can vary the work-rest ratio and exercise durations within the protocol to target different energy systems.

Zone training

 

• • The concept of “zones” (e.g., zone 1, 2, 3, etc.) is used to describe different intensity levels in training, but the distinction between these zones is somewhat arbitrary.

• • Instead of relying on heart rate monitoring, using a breathing “gear system” can help assess intensity levels during exercise. 

 

• • Gear 1: nasal breathing with varied rate 

 

• • Gear 2: and nose-to-mouth or mouth-to-mouth breathing 

• • Gears 3 and 4: maximal effort with pure mouth breathing.

 

• • CO2 tolerance is an important factor in exercise performance, and being able to tolerate and regulate CO2 levels is crucial. High CO2 sensitivity or panic in response to slight increases in CO2 can be problematic, both in exercise and daily life.

• • It is recommended that one should perform one to three rounds of one-minute all-out sprints at least once a week, with two times per week being preferable. Five to six minutes of all-out work per week is ideal.

Aerobic capacity

 

• • Maximum aerobic output training focuses on high-intensity efforts lasting around 5 to 15 minutes.

• • The primary challenge is dealing with waste products and ensuring sufficient oxygen transportation.

• • One-mile tests are a classic way to practice maximum aerobic output.

• • The frequency of training can be once or twice a week for optimal results. Volume and intensity should be balanced, with about 40% of training time spent on lower-intensity support work.

• • It’s recommended to measure progress by tracking the distance covered in a set time period of high-intensity exercise.

• • Rest and recovery should be considered to avoid compromising performance.

• • Combining both maximum aerobic output and anaerobic capacity training can be done by scheduling one of each session per week.

Long duration exercise

 

• • If you hate long classic long duration exercises like cycling, swimming or running, you can
    

     

    • • do circuit training where exercises are combined with minimal downtime between them, 
    • • Rotate through different exercises or machines is another approach to create a steady-state session without monotony.

 

• • Long-duration cardio can enhance the fat-burning system and potentially improve microcapillary systems in muscles.

• • Factors like posture and breathing mechanics should be monitored to avoid technical breakdown and optimize endurance training.

• • You should perform steady state exercise 20-30 minutes once a week to supplement any training protocol

• • Try only nasal breathing during these sessions and finish with a slow 3min walk of slow breathing

Running your first marathon

 

• • The program suggests
    

     

    • • Allocating around 60-70% of training mileage to moderate-intensity runs, focusing on accumulating mileage and building tissue tolerance.
    • • The remaining 30-40% of training time can be divided into different components:
        

         

        • • 10% for short bursts of high-intensity training to drive up fatigue and enhance recovery from waste production.
        • • Some time for maximum speed training, focusing on sprinting as fast as possible.
        • • The rest of the time can be spent on longer durations, such as 5-15 minutes, with repeated intervals like 800-meter runs.

If you made it until now and you are eager to learn more, check out the other episodes from the series:

• Episode 1: How to assess levels of fitness. Check it out
• Episode 2: How to increase strength and muscle mass. Check it out
• Episode 3: You have just read it. It’s this page 🙂
• Episode 4: Optimize your training program for fitness & longevity. Check it out
• Episode 5: Maximise recovery to achieve fitness & performance goals. Check it out