p.17
Testosterone to Cortisol Ratio (T/C Ratio)
What happens to cortisol levels during awakening?
Cortisol levels rapidly rise during awakening.
p.15
Core Body Temperature and Performance
When does the optimal body temperature for strength training typically occur?
In the late afternoon to early evening.
p.31
Effects of Fasting on Muscle Growth
What do systematic reviews say about alternate day fasting and constant daily energy restriction?
Systematic reviews indicate that alternate day fasting and constant daily energy restriction result in similar fat loss.
p.3
Nutrient Timing and Body Composition
What can be deduced a priori about nutrient timing?
It can be deduced that nutrient timing matters, as spreading meals out across the week is more effective than consuming all weekly macros in one day.
p.25
Strategies for Optimal Training Times
How can you determine the optimal time to train?
By monitoring your maximum resting heart rate and training performance.
p.2
Effects of Fasting on Muscle Growth
How does fasting affect muscle growth?
Fasting can affect muscle growth by reducing the availability of nutrients needed for muscle repair and growth, but strategic nutrient timing can mitigate these effects.
p.27
Meal Timing and Metabolic Effects
What are the physiological effects of an irregular meal pattern?
An irregular meal pattern can cause higher fasting total and LDL cholesterol, decreased postprandial insulin sensitivity, and higher blood glucose levels.
p.4
Circadian Rhythm and Training Timing
Besides nutrition, what other factor is important for training?
Biorhythm is also important for training.
p.3
Intermittent Fasting (IF) Overview
Who popularized intermittent fasting (IF) in the bodybuilding community?
Swedish bodybuilding coach Martin Berkhan popularized intermittent fasting (IF).
p.19
Strategies for Optimal Training Times
What is the recommended sleep schedule for optimal training times?
Sleeping during the night from roughly 12:00 – 08:00 h.
p.10
Strategies for Optimal Training Times
Why might personal preference and scheduling convenience make the consideration of training time moot for recreational trainees?
Because it’s much more important to get your workout in than when you do it.
p.30
Meal Timing and Metabolic Effects
Why might having an eating window be suboptimal compared to set meal times?
Having an eating window can cause metabolic disruptions due to the variance in meal sizes and frequency within the window.
p.5
Circadian Rhythm and Training Timing
What have studies found about muscle gains when training in the evening compared to the morning?
Muscle gains can be up to 84% higher when training in the evening instead of the morning.
p.19
Core Body Temperature and Performance
What systemic factors affect the entire body and are regulated by biorhythms?
Core body temperature and hormone levels.
p.25
Circadian Rhythm and Training Timing
Which systems are influenced by your circadian rhythm?
Your sleep-wake cycle, hormonal milieu, gene expression, and core body temperature.
p.2
Effects of Fasting on Muscle Growth
What is the protein sparing modified fast (PSMF)?
The protein sparing modified fast (PSMF) is a type of fasting that focuses on high protein intake to preserve muscle mass while reducing calorie intake.
p.23
Core Body Temperature and Performance
How much caffeine is recommended to achieve results similar to evening workouts when training in the morning?
Over 3 mg/kg of caffeine.
p.20
Strategies for Optimal Training Times
What is the recommended waiting period before training for those with an irregular sleep-wake cycle?
At least 6 hours after awakening.
p.23
Biorhythm Disruption and Health
Can your biorhythm perfectly adapt to early morning training?
No, it cannot perfectly adapt to the extent that performance is 100% unaffected compared to training later in the day.
p.24
Biorhythm Disruption and Health
How can shift workers optimize their biorhythm?
Shift workers can optimize their biorhythm by consistently sleeping during the daytime, training 6-13 hours after awakening, and eating their meals at regular times spread across the day/night.
p.15
Core Body Temperature and Performance
What physical attributes reach their daily peak in the late afternoon to early evening?
Flexibility, power, and muscular strength.
p.15
Core Body Temperature and Performance
Why can greater performance lead to greater muscular adaptations?
Because you can impose more mechanical tension on the muscle fibers to stimulate them to grow.
p.14
Core Body Temperature and Performance
How does a high core body temperature affect physical performance?
High core body temperatures improve nerve conduction velocity, joint mobility, glucose metabolism, and muscular blood flow.
p.25
Strategies for Optimal Training Times
When does peak performance typically occur for individuals working a morning shift?
Before work, followed by lunch, and after work.
p.2
Testosterone to Cortisol Ratio (T/C Ratio)
What is the T/C ratio?
The T/C ratio refers to the testosterone to cortisol ratio, which is an indicator of anabolic (muscle-building) versus catabolic (muscle-breaking) states in the body.
p.2
Individual Variability in Chronotype
Who tends to do well on an intermittent fasting diet?
Individuals who have a natural hunger biorhythm that aligns with the fasting periods tend to do well on an intermittent fasting diet.
p.23
Core Body Temperature and Performance
What happens if you consume more than ~100 mg of caffeine daily?
You’ll develop a tolerance to caffeine’s ergogenic effects.
p.22
Testosterone to Cortisol Ratio (T/C Ratio)
Why might taking caffeine in the morning as a pre-workout not be 100% optimal?
Caffeine decreases the T/C ratio.
p.18
Testosterone to Cortisol Ratio (T/C Ratio)
When is the T/C ratio highest during the day?
In the afternoon and evening.
p.16
Testosterone to Cortisol Ratio (T/C Ratio)
What are the roles of testosterone and cortisol in muscle growth?
Testosterone is anabolic and beneficial for muscle growth and strength development, while cortisol is catabolic and excess levels can be detrimental.
p.30
Meal Timing and Metabolic Effects
Why might skipping meals not always lead to a lower total energy intake?
Skipping meals often results in energy compensation later in the day, where individuals consume the same total amount of energy as if they had eaten the meal.
p.23
Core Body Temperature and Performance
Does caffeine elevate morning growth hormone levels to afternoon levels?
No, caffeine doesn’t elevate morning growth hormone levels to afternoon levels.
p.29
Meal Timing and Metabolic Effects
What is a recommended strategy to maintain a regular biorhythm regarding meal times?
Try to have your meals within 1 hour of their habitual time.
p.29
Intermittent Fasting (IF) Overview
What has research shown about time-restricted daily feeding and alternate day fasting with similar total energy intakes?
They result in equal body recomposition.
p.16
Testosterone to Cortisol Ratio (T/C Ratio)
When does testosterone production peak and decrease?
Testosterone production rises in the evening, peaks very early in the morning, and then decreases across the day.
p.14
Core Body Temperature and Performance
Describe the daily pattern of core body temperature.
Core body temperature is low at night, rises quickly upon awakening, and reaches a maximum in the evening.
p.20
Individual Variability in Chronotype
Can people adapt to morning training, and if so, how?
Yes, some people can adapt to morning training, especially if they consistently wake up and train early over time.
p.11
Circadian Rhythm and Training Timing
What part of the brain acts as the internal or biological clock?
The suprachiasmatic nucleus (SCN) acts as the internal or biological clock.
p.5
Circadian Rhythm and Training Timing
What is the benefit of aligning your training schedule with your circadian rhythm?
You will be stronger, faster, more powerful, recover better, and gain more muscle.
p.29
Intermittent Fasting (IF) Overview
Do intermittent fasting in the morning and evening significantly differ in their metabolic effects?
No, intermittent fasting in the morning and evening do not significantly differ in their metabolic effects.
p.16
Testosterone to Cortisol Ratio (T/C Ratio)
What is the T/C ratio used for?
The T/C ratio is used as a marker of tissue anabolism and a measure of overtraining.
p.4
Nutrient Timing and Body Composition
Does nutrient timing matter for muscle gain?
Yes, nutrient timing matters for muscle gain.
p.32
Effects of Fasting on Muscle Growth
What did multiple studies confirm about time-restricted feeding diets in strength trainees?
Time-restricted feeding diets have similar effects on strength development and body recomposition as diets with constant daily energy restriction with the same average energy and protein intakes.
p.11
Circadian Rhythm and Training Timing
How long is the average cycle of the suprachiasmatic nucleus (SCN)?
The average cycle of the SCN is 24 hours and 15 minutes.
p.12
Biorhythm Disruption and Health
What happens if you try to sleep when it's not bedtime according to your biological clock?
It's hard to fall asleep and your sleep quality is not as good.
p.15
Core Body Temperature and Performance
How pronounced is the circadian rhythm for endurance capacity?
Endurance capacity seems to have a less pronounced circadian rhythm.
p.10
Circadian Rhythm and Training Timing
Why would the time of day affect how much muscle you gain after a workout?
Because of your circadian rhythm.
p.27
Meal Timing and Metabolic Effects
What happens to postprandial metabolism when you eat at times your circadian rhythm is not adapted to digest nutrients?
It causes slight disruption of postprandial metabolism, leading to adverse effects such as higher fasting total and LDL cholesterol, decreased postprandial insulin sensitivity, and higher blood glucose levels.
p.23
Circadian Rhythm and Training Timing
How is muscle growth affected by training in the morning compared to strength development?
Muscle growth is more strongly affected by training in the morning than strength development.
p.12
Biorhythm Disruption and Health
What is the most important zeitgeber?
The most important zeitgeber is light.
p.3
Intermittent Fasting (IF) Overview
What is the LeanGains approach to intermittent fasting?
The LeanGains approach involves 16 hours of fasting and an 8-hour eating window.
p.19
Strategies for Optimal Training Times
What is the best time to schedule training sessions for peak performance if you have a normal biorhythm?
Between 14:30 and 20:30 h.
p.25
Strategies for Optimal Training Times
What is the best time to work out for peak performance and possibly greater long-term gains?
Generally between 14:30 and 20:30 h if you have a regular sleep-wake cycle.
p.27
Meal Timing and Metabolic Effects
What is the main difference between people who have a regular breakfast routine and those who do not?
People with a regular breakfast routine have a plan, while those without a plan are more likely to snack and consume convenience foods.
p.23
Strategies for Optimal Training Times
What is the second strategy to increase performance when training at a suboptimal time?
Consistency in training at that time.
p.20
Individual Variability in Chronotype
What is a 'chronotype'?
A chronotype is an individual's natural inclination regarding the times of day they prefer to sleep or be active.
p.11
Circadian Rhythm and Training Timing
How does the SCN influence other systems in the body?
The SCN interacts with virtually every major system in the body, including hormone production and central nervous system activity, which have their own peripheral clocks that listen to the master clock.
p.12
Biorhythm Disruption and Health
What are 'zeitgebers'?
'Zeitgebers' are 'time givers' that entrain your biological clock.
p.31
Effects of Fasting on Muscle Growth
Does fasting impact fat loss if total daily protein and energy intake are the same?
No, there is no difference in effectiveness between intermittent or constant energy restriction for fat or weight loss.
p.2
Core Body Temperature and Performance
How does core body temperature affect performance?
Performance tends to be better when core body temperature is higher, which usually occurs in the late afternoon or early evening.
p.20
Strategies for Optimal Training Times
Why might the optimal training time be closer to 20:30 h than 14:30 h for some individuals?
Because of the variability in individual chronotypes and biorhythms.
p.16
Testosterone to Cortisol Ratio (T/C Ratio)
Why should testosterone bloodwork be done in the morning?
Testosterone bloodwork should be done in the morning (fasted) to get comparable results due to testosterone's strong biorhythm.
p.2
Strategies for Optimal Training Times
What are some strategies if you can't train at the optimal time?
Two strategies include using caffeine to boost performance and maintaining consistency in training times to adapt your body.
p.2
Biorhythm Disruption and Health
What are the effects of biorhythm disruption on health?
Biorhythm disruption can lead to various health issues, including metabolic disorders, sleep disturbances, and decreased overall well-being.
p.20
Individual Variability in Chronotype
How do 'early birds' and 'night owls' differ in terms of performance loss in the morning?
Early birds show far less loss of performance in the morning compared to night owls.
p.24
Strategies for Optimal Training Times
What is more important than the specific time of training?
Consistency in training time is more important than the specific time of training.
p.24
Biorhythm Disruption and Health
What is the key to managing uncommon schedules for sleep, training, and eating?
The key is to find consistent times for sleep, training, and eating, regardless of when they occur.
p.24
Biorhythm Disruption and Health
What should be done if shift hours change frequently?
The schedule should aggressively change along with the change in work hours to adapt the biorhythm, similar to adjusting to a different time zone.
p.11
Circadian Rhythm and Training Timing
What role does the biological clock play in the body's systems?
The biological clock tells all the systems in the body what time it is, influencing when they become more active and how they function.
p.12
Biorhythm Disruption and Health
How does the SCN use light to determine your sleep-wake cycle?
The SCN uses the intensity of light to determine where you are in your sleep-wake cycle.
p.21
Strategies for Optimal Training Times
What is one strategy to counteract not being able to train at the optimal time?
One strategy is to use caffeine, which forces your body into daytime mode.
p.10
Strategies for Optimal Training Times
What is the overall trend of research regarding the best time of day to exercise?
It suggests it’s slightly better to exercise in the afternoon or evening instead of the morning.
p.2
Circadian Rhythm and Training Timing
What is the optimal time to work out according to circadian rhythm?
The best time to work out is typically in the late afternoon or early evening when core body temperature is highest.
p.2
Intermittent Fasting (IF) Overview
What is intermittent fasting (IF)?
Intermittent fasting (IF) is an eating pattern where you cycle between periods of eating and fasting.
p.23
Circadian Rhythm and Training Timing
Which adapts better to early morning training: the nervous system or physiological systems?
The nervous system adapts reasonably well, but physiological systems such as hormone production adapt less well.
p.24
Strategies for Optimal Training Times
When might it be better to train during lunch rather than after work?
It may be better to train during lunch if you have a physically demanding job, as fatigue from work may offset the benefits of training later in the day.
p.28
Meal Timing and Metabolic Effects
How does eating at irregular times affect the thermic effect of food (TEF)?
It results in a lower TEF due to decreased insulin sensitivity.
p.11
Circadian Rhythm and Training Timing
What is a circadian rhythm?
A circadian rhythm is a daily cycle of biological activity, such as the sleep-wake cycle, regulated by an internal clock in the body.
p.12
Biorhythm Disruption and Health
What does the SCN influence in your body?
The SCN influences when various systems in your body become active.
p.24
Strategies for Optimal Training Times
What should you do if your work schedule prevents you from training in the afternoon?
If your work schedule prevents you from training in the afternoon, prioritize getting in your workouts whenever you can.
p.12
Meal Timing and Metabolic Effects
What can result from eating at irregular times?
Eating at irregular times can result in suboptimal metabolic effects.
p.20
Core Body Temperature and Performance
How can heart rate be used to determine the best time to train?
The time of day when your resting heart rate peaks is often the best time to train.
p.21
Strategies for Optimal Training Times
How much caffeine is suggested to raise neuromuscular readiness to perform close to afternoon levels?
A dose of ~250 mg (3 mg/kg) caffeine in the morning is suggested.
p.9
Circadian Rhythm and Training Timing
How do elderly individuals' fatigue levels and perceived exertion during exercise vary throughout the day?
Elderly individuals are more fatigued later in the day and experience higher perceived exertion during exercise compared to the morning.
p.12
Biorhythm Disruption and Health
What is an extreme example of chrono-disruption?
Jetlag is an extreme example of chrono-disruption.
p.24
Circadian Rhythm and Training Timing
What can help shift your optimal training time greatly?
Meticulous circadian rhythm control using supplementation, light therapy, and consistent nutrition and training can help shift your optimal training time greatly.
p.24
Strategies for Optimal Training Times
What is the impact of training at different times of the day on strength or muscle gains?
The difference in strength or muscle gains when training at different times of the day is small, as long as you consistently train at the same time.
p.28
Biorhythm Disruption and Health
What happens to cortisol production when the circadian rhythm is disrupted?
There is an increase in total cortisol production across the day.
