A focused training program can increase your VO2max by 15 to 30% over a 3 month period and up to 50% over 2 years. And the converse is true as well. There is a drop off in metabolic adaptations within a few weeks of stopping training although changes in numbers of muscle capillaries and skeletal and cardiac muscle fiber size probably occur more slowly (see detraining below).
Metabolic adaptations facilitate lactic acid removal allowing you to perform exercise at a higher level of %VO2max for longer periods of time, and changes in lipid metabolism which will provide extra Calories from fat to supplement those from glycogen and glucose metabolism for any specified level of activity (%VO2max). The result is an increase in maximal performance and the ability to maintain a high level of performance for a longer time interval (endurance).
Training also improves the muscle's tolerance for the stresses of prolonged exertion. These include strengthening of the connective tissue between muscle fibers to minimize the microtrauma (and post exercise discomfort) that occur with with physical exertion. Not every training session (in your program) needs to stress the cardiovascular system. In fact a successful program needs to be balanced with at least two days per week at less than maximal cardiovascular intensity to allow formental and physical recovery. And it has been demonstrated that your performance in a competitive event is better if you taper your training program in the week prior.
But before we get into the advanced course on training techniques, let's not forget our basics. If it is early in the riding season, or you have just decided to get back into riding again, the secret to preventing injuries and preparing yourself to get the most out of the training tips that follow, is to develop a good, personal mileage base. You may be fortunate enough to live in warmer, dryer climes, or been able to drag yourself to a spin class all winter. If not, the first order of business for the training year is to put some unstressed (no intervals, no sprinting up hills) miles on your bike (and body). It's not that intervals or hills are forbidden - but not too hard or too often. Remember, you're still banking foundation miles for the season. The best strategy is to let the terrain and how you feel (perceived exertion) tell you when to make that effort. If, at the end of the long ride, you feel like you could go out and put in a few more miles - you are probably doing it just right. A good target is a base of 500 miles - and as a rule of thumb, don't increase your weekly mileage by more than 10% as you are getting there.
Is more better? Not necessarily. The exact optimum for training intensity varies by a few percent between individuals (that's why coaches can help find that extra few % of a performance advantage for an elite athlete. It is generally accepted that maximum aerobic improvement occurs at 85% VO2max (approximately 90% of your max. heart rate), and REGULAR training above this level will increase the potential for injury without a corresponding benefit in cardiovascular (or musculoskeletal) adaptation. Lower levels of exercise - 60% maximum heart rate for 45 minutes or 70% maximum heart rate for 20 minutes - will modestly improve (or at least maintain) general cardiovascular conditioning but the use of the "long slow distance" approach where your maximum heart rate is always kept at 60 to 80% VO2max will not optimize your personal performance for high level aerobic events. For example, a West Virginia U. study assigned 15 women to either a low intensity (132 beats per minute) or high intensity (163 bpm) group exercising for 45 minutes, 4 times a week. There was an increase in VO2max for members of the high intensity group, but not the low intensity one.
The optimum duration for a training session depends on the intensity. Ten minutes of 70% maximum heart rate will be of some benefit, but 30 to 40 minutes are even better. Does going 60 minutes give you a proportionally greater benefit? Maybe not as there is some point at which the negative effects of exercise on breaking down and injuring muscle tissue outweight the cardiovascular benefits. Does 30 minutes of 80% MHR equate to 40 minutes at 70% i.e. increase the intensity to compensate for decreasing the duration? For endurance perhaps, but certainly not for improving your VO2max.
As proof that there is an upper limit for the benefits of aerobic training, a group of swimmers training 1.5 hours per day was compared to a group training with two equivalent 1.5 hour sessions. There was no difference in the final performance, power, or endurance between the two groups. For aerobic training (continuous, not intervals) at less than 90% maximum heart rate it makes the most sense to look at the duration of the planned event, and train
- at the same level of anticipated performance (%VO2max)
- for a duration (distance) equal to 110 - 120% of the event
It appears that maximum aerobic conditioning (increasing VO2max) occurs with 3 workout days per week. So unless one is trying to burn Calories to lose weight, or is working on increasing mileage to get the musculoskeletal system (back, shoulders) in shape for a long endurance event on the bike, it is better to take off 2 to 3 days per week to allow for muscle and ligament repair and decrease the risk of cumulative stress resulting in an increase in training injuries. And interestingly, it appears that these 3 days per week will maximize aerobic conditioning equally in any combination - i.e. 3 days in a row with 4 off, alternating days of exercise, etc.
Q. I was reading the other day in Joe Friels Cyclists Training Bible, he briefly mentions that training twice a day is better because you release a second dose of growth hormone during the day. I haven't found any literature behind his comment. Have you got in more info about training twice a day compared to once? - J.
A.I am unaware of any literature that supports twice a day training except as a way to work around a limited schedule (such as work committments). In fact I would suspect that if there is any effect it would be a negative rather than a positive compared to a single longer session.
Studies on maintaining the benefits of aerobic training revealed that a 2/3 reduction in training frequency i.e. going from 6 days a week to 2 days a week (keeping the same maximal intensity for each individual workout) maintained the gains. You can cut a 60 minute, 6 per week program to 60 minutes, 2 times a week and maintain your aerobic fitness level, BUT you CANNOT maintain a similar fitness level by cutting the intensity of the 60 minute session and keeping it at 6 times per week. If intensity is held constant, the frequency and duration of exercise required to maintain fitness are much less than the effort needed to attain that fitness level in the first place.
METHODS OF TRAINING
Training needs to be structured for the intensity and duration of the planned sporting event. Anaerobic (oxygen independent) exercise is generally brief (less than 60 seconds in duration) and is fueled by the anaerobic energy pathways in the cell (ATP, creatine phosphate). The classic anaerobic sport is weightlifting. Sprint activities also use anaerobic pathways. If the sprint lasts more than 5 or 10 seconds, lactic acid production (and clearance) also becomes an issue because of the negative effects of lactic acid on muscle performance. Training focused on anaerobic activities will enhance the ATP and CP energy transfer pathways in the cell as well as improving the tolerance for and clearance of lactic acid.
Aerobic training (more important for cycling and other sporting events lasting more than 60 seconds) on the other hand provides its benefits by improving the cardiovascular and oxygen delivery systems to the muscle cell. These include improvements in both cardiac output (amount of blood pumped by the heart per minute) and at the muscle fiber level where there is an increase in the removal or extraction of oxygen from the blood cells in the capillaries. In addition, there is an improvement in the efficiency of the cellular metabolic pathways which convert glucose into ATP.
As the level of exertion (measured by %VO2max) increases, there is a slow transition towards anaerobic metabolism in the muscle. There are always areas of relatively lesser perfusion within the muscle that are functioning anaerobically. So even at 50 to 60% VO2max some anaerobic conditioning is occuring. But at 85% VO2max (the "anaerobic threshhold" for most individuals) there is an abrupt increase in anaerobic metabolism throughout the entire muscle. So even though some cross training of the anaerobic systems takes place during exercise at 60 to 80% VO2max, a training program for sprint performance needs to include several exercise sessions per week above 85%VO2max. Long slow distance may be good training for aerobic, endurance events, but it will not improve your sprint performance. Both aerobic and anaerobic exercise sessions need to be included in a training program, but it is the balance of the amount of each type of exercise (aerobic vs anaerobic; interval training, continuous training, and fartlek training) in the overall program which determines its suitability for the competitive event for which you are training.
Doing intervals refers to sandwiching periods of intense physical activity between periods of recovery to allow longer periods of training time at your peak performance levels. One study in runners demonstrated that continuous, maximal performance levels could be sustained for only 0.8 miles before exhaustion occurred, while a similar level of peak exertion could be maintained for a cumulative distance (duration) of over 4 miles when intervals were used.
If one is training for sprints of up to 20 seconds in duration (which do not involve significant lactic acid buildup and basically are training the ATP and CP systems), it is recommended that the duration of the training interval should be increased by 1 to 5 seconds over the usual best time for that sprint distance with exercise intensity or maximum effort being unchanged,. For example, if one is training for a 100 yard dash, and has a personal best of 12 seconds, the training interval should be a 13 or 14 seconds sprint at the same pace (ignoring the total distance being covered in the 13 or 14 seconds). And a relief period 3 times longer than the training interval is recommended for recovery - 42 seconds in this example.
Training for longer intervals (up to several minutes) produces significant lactic acid along with stressing the anaerobic metabolic pathways. To train for these longer distances (several minutes of maximum output), it is suggested that the distance being trained for be subdivided, and the training interval effort focused on that shorter distance. For example, if one is training for a personal best mile ride on the bike, and the best time for the entire mile is 3 minutes on the bike with the best 1/4 mile segment being 30 seconds and the best 1/2 mile segment being 80 seconds, the training interval could be set at either 1/4 or 1/2 mile and the time for this training interval set at your personal best minus 3 to 5 seconds. In this example the training interval might be chosen as 1/4 mile with a goal of a 25 second time. And the rest interval should be 2 times the training interval (as lactic acid clearance does not require the same recovery time as recharging the intracellular metabolic machinery).
But training program drop out rates can double when intervals are used, so they should be used judiciously. Don't use them all year round, consider a twice a week program during your peak season, and separate each session by at least 48 hours to allow adequate recovery. If your long ride is on the weekend, Tuesday and Thursday make the most sense. The goal should be 10 to 20 minutes of hard pedaling per training interval session, not counting warm up, recovery, or cool down. A good place to start is with 5 minutes of peak effort.
One approach is to use one day a week for short intervals (i.e. five 60 second and five 90 second intervals) and a second for longer intervals (two 3 minute and two 5 minute intervals). Allow 3 to 5 minutes for recovery between intervals and don't forget a 20 to 30 minute warm up and a 15 minute cool down. It has been shown that as few as a half dozen 5 minute intervals (separated by one minute recoveries) during a 300 km training week will improve both time trial and peak performance.
If you have a heart rate monitor, an alternative is to key intervals to your maximum heart rate. Ride your intervals at 80 to 90% of your maximum heart rate and spin easily until your heart rate drops to 60 to 65% of maximum.
CONTINUOUS TRAINING (LSD)
Continuous training refers to aerobic activity performed at 60 to 90% VO2max for an hour or more. When done at the lower end of this range, it is often referred to as long, slow distance (LSD) training. This level of training is ideal for those starting off an exercise program, those wishing to maximize Caloric expenditure for weight loss purposes, and as an option for an active "rest" day in a weekly aerobic training program.
This level of exertion can be maintained for hours at slightly less intensity than used in personal competitive events in the past, and is particularly suited for endurance event training. It is thought to have a preferential beneficial effect on the slow twitch muscle fibers (as opposed to the fast twitch fibers used in sprint interval training). It is suggested that a distance of 2 to 5 times the actual competitive event be chosen for this daily segment of the weekly training program.
This form of training is a combination of interval and LSD training. It is not as structured as an interval program being based on the personal perception of exertion rather than specific time or distance intervals. It mimics the "sprint to the line" that is part of many road races. While there is little scientific proof of its benefits it makes sense physiologically, and psychologically it adds a feeling of freedom to those long slow days. How many sprints, and for how long?? The choice is up to you, but the intervals are probably in the neighborhood of those used for interval training.
KEY POINTS FOR AN AEROBIC TRAINING PROGRAM
- Training needs to be structured for the intensity and duration of the planned sporting event.
- Long slow distance training is important at the beginning of the training season and for very long endurance events.
- Maximum aerobic improvement occurs at 85% VO2max (90% max. heart rate).
- Maximum aerobic conditioning (increasing VO2max) occurs with 3 workout days per week at or above 85% VO2max. Additional training days should be at a slower pace to allow recovery and build musculoskeletal strength.
- Intervals can be ridden for one or two of these days.
- Exercising at less than 85% VO2max will improve general cardiovascular conditioning and overall musculoskeletal tolerance. It is suggested that one day a week be alloted to a long slow training ride equal to a distance of 2 to 5 times the actual competitive event.
- In training for endurance events (less than 90% maximum heart rate), train at the level of anticipated performance (%VO2max, %MHR)) and with a long training ride equal to that of the event + 10 to 20%.
(see also USING A HEART RATE MONITOR)
PUTTING THIS ALL TOGETHER, a good weekly training program:
- is built on a good training base at the beginning of the season.
- 3 days of high level cardiovascular activity (2 of which may be intervals)
- 1 day training ride equal to the duration of the event and at a similar intensity
- 1 day LONG slow recovery ride
- the other 2 days should be spent off the bike or used for a short slow ride to "loosen up"
Aim for a total time committment per week of 10 hours. It's interesting that two of America's all-time great road riders, Greg LeMond and Connie Carpenter, both recommend the same total weekly training time -- 10 hours -- for fast recreational riders. They say if you devote that much to a mix to distance, speed, climbing and easy rides for recovery, you're likely to come close to your potential. And time on the bike seems to be the key, not the miles ridden. Lemond's Law is occasionally referred to in bike magazines. To paraphrase: when you record your daily workout, make your key entry the time you rode not how far you rode. The reason, says Greg, "twenty miles into a headwind is a lot different than 20 miles with a tailwind". The same holds for a ride in the hills vs. a ride on flat ground.
For most recreational roadies, 7-10 hours of riding per week is plenty for steady improvement if you have an intelligent training program.Wouldn't more be better? If you do try to add in extra hours, you risk bothy overtraining as well as the extra stress produced by more time on the bike. Both physical stress on your body and the pressure it puts on responsibilities to family, friends, and profession.