• need high type two fibres (fast twitch)
• must be strong but light as well
Adaptive to control ratio (training vs. no training)
Cross sectional area of ST fibres: Even if you are untrained you will see an increase in fibre
size, but it is relatively limited 6 months builds enough strength for the activity and adaptation
Max VO2: large increase in first year slower increase 2 year
Capillaries: dormant capillaries will open up and more will be formed
Oxidative fibres: must be doing higher intensity training, large increase in first year.
Kreb’s cycle enzymes: more than double
With no training over 6 months, everything will come back down to baseline.
To quantify the rate, it is a mirror image of the time you spent
training. The longer you have been doing the sport, the longer it
takes for you to detrain. Frequency, Duration and Intensity of Training Reduction
How these will effect detraining
Trained 6 times a week, 3 days 5x5 minutes, 3 days 3x40
minutes (max heart rate was achieved)
What happens if we reduce each of these things individually?
Frequency: 4 times a week vs. 2 times a week
found there was no change in their VO2 max.
• As long as you maintain the duration and intensity, you can
cut back on the number of times a week and still maintain your
Duration: 1/3 of the time vs. 2/3 of the time
No change in VO2 max
Intensity: 2/3 intensity vs. 1/3 intensity
VO2 max/ fitness will decrease.
Getting and maintaining fitness requires high intensity the entire time.
You can decrease duration and frequency as long as you maintain intensity.
ATP-PCr (2-10 seconds) and anaerobic glycolysis (20 -90 seconds)
Weights effective in overloading the muscles – increasing strength (contractile tension) is at 3-8
• Working with high repetitions trains energy systems, low repetitions increases strength
by maximally activating all fibres.
With resistance training leading to increased muscle mass, aerobic capacity of muscle actually
With hypertrophy and increase in contractile proteins, you must continue with aerobic
training to keep aerobic capacity, or there will be less capillaries per fibre.
Increase in creatine kinase (CK) P + C PCr
Increase in myokinase (MK) 10-15% ADP + ADP ATP + P
Increase in ATP and PCr 25-40%
Increase ability to use glycogen (glycolysis)
Oxidative Kreb’s Cycle enzymes
Carnitine… breakdown of fats
How do each of these respond to training or
For it to adapt it must be recruited during the