Muscle Bio Week 6.docx

***Week 6, Module 6: Skeletal Muscle Adaptations to Endurance and Resistance Training*** - Specificity: adaptations to training are highly specific to the type of exercise performed. - Endurance training: cardio based activities that are typically low force and long duration - Resis...

***Week 6, Module 6: Skeletal Muscle Adaptations to Endurance and Resistance Training*** - Specificity: adaptations to training are highly specific to the type of exercise performed. - Endurance training: cardio based activities that are typically low force and long duration - Resistance training: BW or external load that is repeatedly lifted through a range of motion. High force and short duration activities. - The 2 modalities above are at 2 different ends of the Intensity/Duration training spectrum. - For endurance, it is represented as VO2max and for resistance, it is 1RM - Sports will have different requirements of each of the modalities, with some sports required the athlete to be trained in both.   Video questions to answer (sports analysed are Tour de France and Strong Man Comp) 1. What are the **differences in the physiological demands** between these sports?  2. In particular, think about the **characteristics of the muscle activity** required (consider the intensity and duration of the muscle activity) 3. What are some of the **adaptations** that will likely have occurred in the muscles of these athletes to allow them to cope with the physiological demands of these sports?   *Specificity of Exercise Adaptations* - Endurance training = more metabolic stress. Due to the high energy demand that needs to sustain repeated muscle contraction at a low to moderate intensity for a prolonged period - Resistance training = more mechanical stress. This is due to heavier forces being lifting by the muscles for reps.   Adaptations within the muscle to endurance training - Capillarisation: increased number of capillaries, which increases blood flow and metabolic fuel supply to the muscle - Increased fuel storage: more CHO and FAT reserves - Mitochondria: increased amount = increased capacity for aerobic ATP production - Smarter fuel use: increased capacity to use fat as a metabolic fuel and spares CHO for use later in exercise   Adaptations within the muscle to resistance training - Increased whole muscle size: Increased size of individual muscle fibres - Increased muscle fibre size: aka hypertrophy. Due to increased contractile protein content. Growth occurs in type 2b fibres. - Increased force transfer protein content: increase in structural proteins involved in force transmission within and out of the muscle fibre - Increased strength: due to muscle hypertrophy and neural adaptations   EXERCISE MUSCLE CONTRACTION PHYSIOLOGICAL STRESS PHYSIOLOGICAL ADAPTATION ------------ ------------------------------- ---------------------- ------------------------------------------------------------------------------ Endurance Low force, prolonged duration Metabolic stress Increased fuel supply, fuel storage, fuel utilisation and fatigue resistance Resistance High force, short duration Mechanical stress Increased muscle hypertrophy, strength and force output.   - HIIT training sits somewhere in between, however it tends to create more metabolic than mechanical stress due to the lighter loads used. So, it will not result in as much strength gain as resistance training, however tends to promote more endurance based adaptations. - Tends to be a more time efficient method of training.   *Are adaptations completely distinct?* - Training adaptations can be viewed on a continuum. You can still obtain hypertrophy of the type 1 fibres from prolonged endurance training and resistance training can help to improve mitochondrial function. There overlap is true in the early stages of exercise, when the participant is untrained. As the participant becomes more trained, the adaptations and responses to exercise become more refined.