Based on Lindsay and SolarEnergy's encouragement, I did some more reading on respiration to see if my beliefs that training anaerobic at equivalent energy levels would work the aerobic system just as hard.
I think I was wrong, anaerobic interval training alone will not tax the aerobic system optimally for a swimmer.
No math, promise. Here is some of what I learned.
Energy production is localized. For example, the muscles in your arms can become more efficient, while your legs do not. The adaptions caused by training happen on a per cell level, and if a cell isn't being worked, it has no reason to adjust. This is obvious every time one of us who is in shape goes and does something new, and is quickly winded and sore the next day. The "but I thought I was in shape" phenomenon.
If a muscle is getting any anaerobic energy, then it is at 100% aerobic capacity. If a muscle has oxygen, it is going to use it.
Sugar is converted to anaerobic energy much less efficiently than aerobic. If you drive a car in aerobic mode and get 20 miles to the gallon, anaerobic mode is about 1 mile to the gallon.
Lactate is a waste product to anaerobic energy production.
Lactate is recycled after oxygen becomes available. The recycling process requires energy that is provided aerobically.
Lactate recycling takes about 3x as much energy as it provided originally, so there is a lot of post exercise aerobic work being done.
Although a lot of aerobic energy is needed to convert lactate back to sugar, this process isn't done in your swimming muscles, and does not benefit your aerobic swimming at all.
Taxing the lactate recycling system (that happens in the liver) will help you recover faster as your liver adapts to processing larger volumes of lactate. The aerobic benefits caused by anaerobic energy production are really next event benefits, not this event benefits.
In another thread, Rich Abrahams mentioned that Michael Mann told him to do a controlled 30 minute swim at an aerobic level. I didn't understand why at the time but I think I understand now. Interval training gives the aerobic system in the swimming muscles a break. An occasional long slow swim (I think Rich said he did it weekly) would encourage adaption of the aerobic system specifically in the swimming muscles. If Rich or Michael wants to explain the real justification, I would love to hear it.
Here are my opinions on training right now
Long uninterrupted swims are probably the best for improving aerobic conditioning where it matters.
The majority of training time should be devoted to anaerobic work.
I don't see any benefit to swimming intervals at aerobic pace over swimming aerobic pace continually.
I don't see what beneficial adaption would occur when extreme over distance training (>x4 target event).
Based on Lindsay and SolarEnergy's encouragement, I did some more reading on respiration to see if my beliefs that training anaerobic at equivalent energy levels would work the aerobic system just as hard.
I think I was wrong, anaerobic interval training alone will not tax the aerobic system optimally for a swimmer.
No math, promise. Here is some of what I learned.
Energy production is localized. For example, the muscles in your arms can become more efficient, while your legs do not. The adaptions caused by training happen on a per cell level, and if a cell isn't being worked, it has no reason to adjust. This is obvious every time one of us who is in shape goes and does something new, and is quickly winded and sore the next day. The "but I thought I was in shape" phenomenon.
If a muscle is getting any anaerobic energy, then it is at 100% aerobic capacity. If a muscle has oxygen, it is going to use it.
Sugar is converted to anaerobic energy much less efficiently than aerobic. If you drive a car in aerobic mode and get 20 miles to the gallon, anaerobic mode is about 1 mile to the gallon.
Lactate is a waste product to anaerobic energy production.
Lactate is recycled after oxygen becomes available. The recycling process requires energy that is provided aerobically.
Lactate recycling takes about 3x as much energy as it provided originally, so there is a lot of post exercise aerobic work being done.
Although a lot of aerobic energy is needed to convert lactate back to sugar, this process isn't done in your swimming muscles, and does not benefit your aerobic swimming at all.
Taxing the lactate recycling system (that happens in the liver) will help you recover faster as your liver adapts to processing larger volumes of lactate. The aerobic benefits caused by anaerobic energy production are really next event benefits, not this event benefits.
In another thread, Rich Abrahams mentioned that Michael Mann told him to do a controlled 30 minute swim at an aerobic level. I didn't understand why at the time but I think I understand now. Interval training gives the aerobic system in the swimming muscles a break. An occasional long slow swim (I think Rich said he did it weekly) would encourage adaption of the aerobic system specifically in the swimming muscles. If Rich or Michael wants to explain the real justification, I would love to hear it.
Here are my opinions on training right now
Long uninterrupted swims are probably the best for improving aerobic conditioning where it matters.
The majority of training time should be devoted to anaerobic work.
I don't see any benefit to swimming intervals at aerobic pace over swimming aerobic pace continually.
I don't see what beneficial adaption would occur when extreme over distance training (>x4 target event).
