Lecture 9 - Nutrition and Training Adaptations Flashcards
why do we need to consider nutrition with training adaptations
- if we don’t have the materials, we can’t adapt and maybe even decline
- adaptations to exercise or exercise training are specific to the exercise performed
*resistance exercise results in muscle hypertrophy, making the muscle stronger
*endurance training results in an increased oxidative capacity, making the muscle more fatigue resistant
how are training adaptations initiated by genes and DNA
- TA in skeletal muscles may be generated by the cumulative effects of transient increases in gene transcription during recovery from bouts of exercise
- the process of exercise induced adaptations in muscles starts with a specific molecular event that triggers protein synthesis
- signaling mechanisms triggered by exercise stress initiate replication of DNA gene sequences that enable subsequent translation of the genetic code into mRNA and a series of AA to synthesize new proteins
what does it mean to “train low”
training with a lower available amount of a particular substrate
- theoritically can increase metabolic gene transcription and it is suggested that the body can modify its response to this training (optimize usage, use less)
- although there is some recent studies that suggest that training with low glycogen could have some metabolic advantages, improvements on performance is not clear
reasons why training low is bad
- the type of training is going to be harder, recovery takes longer
- risk of overreaching/overtraining is greater
- immunodepression may be more profound
- therefore, the use of training with low carb availability may be considered but need to be applied with caution and may be used only one or two times per week
is training without breakfast the best “fast burning” protocol for endurance athletes
endurance athletes have used exercise without breakfast as a way to increase the oxidative capacity of muscle
- ingesting carbs in the hours before exercise will raise plasma insuling and subsequently suppress fat oxidation by up to 35%
- This effect of insulin on fat oxidation may last as long as 6
to 8 hours after a meal, and so the highest fat oxidation
rates can be achieved after an overnight fast.
ITS THEORETICALLY FAT BURNING BUT YOU WILL HAVE IMPACTED PERFORMANCE
- consider the differences of exercises in a fasted state vs low glycogen state
why is leucine important in protein synthesis
- is an essential AA that is a signalling molecule as well as a building block for protein synthesis
- although leucine alone can stimulate the signals in the muscle to increase rate of protein synthesis, this increased signalling will not result in increased synthesis if other AAs are not available
- following a bout of exercise, protein synthesis is maximized by the ingestion of 0.4g/kg/bw of high quality, rapidly digested protein containing 3g of leucine (i.e. whey proteins)
how do antioxidants blunt training adaptations
- the ROS produced during exercise training act as signals for training adaptations
- anti oxidants supplementation interfere with these adaptations (increases in mitochondrial biogenesis)
how do NSAIDS impact training adaptations
- non-steroidal anti-inflammatory drugs (i.e. ibuprofin, asprin, naproxen) are the most widely known therapy in treating muscle damage
- NSAIDS interfere with the normal inflammatory response after damaging exercise, it is possible that the inflammatory process plays a role in the adaptation that occurs postexercise
- they should not be a recommended strategy to treat symptoms of muscle damage
overreaching
an accumulation of training or nontraining stress resutlting in a short term decrement in performance capacity with or without related physiological and psychological signs of symptoms of overtraining
- restoration of performance capacity takes days to weeks
overtraining syndrom
an accumulation of training and nontraining stress resulting in long term decrements in performance capacity with or without related physiological and psychological signs and symptoms of overtraining
- restorations of performance may take months
symptoms of overreaching and over training
DECREASE IN PERFORMANCE
- weeling tired, drained, lack of energy
- pain in muscles and joints
- decreased immunity
- loss of enthusiasm for the sport
- eating problems
- reduced maximal lactate, heart rate
relate nutrition and sleep
- sleep quantity and quality are important for athletes because of its numerous physiological and cognitive function that may be particularly important for physical and mental performance
- athletes often experience reduced quality and/or quantity of sleep during periods of intensified training
- poor sleep quality is associated with tiredness, irritability, impaired performance and impaired immunity
nutritional strategies to improve sleep quality
- high glycemic index foods (white rice, pasta, bread, potatoes) may promote sleep; they should be consumed more than 1hr before bedtime
- diets high in carbs may result in shorter sleep latencies (i.e. less time to fall asleep)
- diets high in protein ay result in improved quality
- diets high in fat may negatively influence total sleep time
- when total caloric intake is decreased, sleep quality may be disturbed
- tryptophan (1g) may improve sleep latency and quality. These effects can also be replicated by consuming 300g of turkey
- melatonin may decrease sleep onset time
- subjective impacts of the herb valerian on sleep quality
how can diet/nutrition prevent overtraining
- high carb intake during periods of intensified training can DELAY and/or REDUCE the magnitude of overreaching symptoms, such as decreased performance, reduced endocrine responsiveness to exercise, and disturbed mood state
- a high carb diet cannot prevent over reaching
how can nutrition impact injury rehab
- nutritional needs are different based on what we are rehabbing
- focus on nutrient that can improve skeletal muscle regeneration by targeting key functions of immune cells, muscle cells or both
these nutrients include: - AAs
- N3 polyunsaturated FAs
- polyphenos
- vit D (1000 to 4000 IU)
- 1-2g of O3FAs
