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CYCLING PERFORMANCE TIPS
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Last updated: 5/5/2012
The Facebook Project -Training with Luqman
A step by step review for a new cyclist
I frequently get questions on designing personalized training
programs. Although all the necessary information can be found on various pages
of my website, those of you just getting serious about cycling need a better way
to pull it all together and make it relevant for your own goals in riding.
When I received the following question on the
CPTIPS Facebook page, it seemed like a good time to walk through the process,
step by step, to develop (or modify) a personal training program.
As I get feedback and comments (send them to me at
CPTIPS feedback), I will revise and
add to this specific webpage.
The Luqman Project
"My name is Luqman. I am a 16 year old student.
I got my road bike in December, 2011. I have been joining group rides occasionally
from the end of December until now - about 150 miles total. I think I am doing well but
I have not seen any improvement. So the group rides I was joining are quite fast,
at least for me although it's only 15 miles, and occasionally 35 miles.
I have been dropped a few times but it was not
consistent. I felt that I didn't improve anything on cycling, and I really
need to have some help from the experience.
I have a very beginner road bike, with carbon forks and aluminum frame,
equipped with Shimano 2300 8 speed. As for now, I can't afford things
like jersey/short, cyclocomputer, shoes but I have a helmet to get me started.
I usually use my normal shorts to cycle.
I live in South-East Asia, the weather here are hot and wet through out
the year, the terrains near my place are mostly flat but there are quite a lot
of hills if I go further away outside the city. I really need some experienced
advice or training plans to help me improve. Even though we couldn't meet,
I hope you can be my coach. Thank you."
Although it may seem trite, attitude is a major factor in reaching your personal
best on a bike. There will be days that you want to cut short your ride, and
others where it seems your goal is quite a distance away. Although there are
physical characteristics that are common to elite
cyclists, more often it is attitude, coupled with a sound training program, that
will make the difference in reaching a personal goal. Persistence counts --
and although twelve weeks of training will get you into good riding shape,
it will take years to reach your personal best.
The flip side is that attitude alone will not get you to your goal.
Success requires incorporating many of the tips that follow on this page (and
elsewhere on the website) into a personal training program - a systematic
program based on sound principles of physiology. There will be periods of
frustration, but overcoming that frustration is what separates the world
class riders from those that are just "very good".
This email tells me that Luqman has the first and most basic requirement to
become a better cyclist - the desire to be among the best.
A good mileage base is the foundation of a successful training program,
important if you want to avoid the types of injuries that keep one from
riding that season. So take it slow at first.
If it is early in the riding season, or you have just decided to get back into
riding after a period off the bike, you are probably feeling pretty frisky and
the tendency is to push yourself. But 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 -
just keep them reasonable and not too hard or too often.
Remember, you're banking foundation miles for the season. The best strategy at
this point in the training year is to let how you
feel on the bike (perceived exertion) tell you when
to add that additional effort. If, at the end of the long ride, you feel 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 total weekly mileage by more than 10% over the prior week
as you are getting there.
Q."I'm doing base training of 25 miles. Half of the distance is riding
into the headwind, and the other half is with tailwind. So, I managed to
maintain good high cadence.. so when I'm riding the other half of 25 miles
base training, I'm going fast (I think)... around 19-22 mph.. am I too fast
for base miles? Am I doing it wrong? But I felt I can maintain good breathing
and high cadence, does that mean it's okay?"
A.Remember, the reason you are riding within the limits of comfort is to
minimize the chances of an injury during this early season riding. You will
have plenty of opportunities to push your limits once we get into a structured
training program. As long as you are feeling good, it is fine. As time goes along,
you will naturally get faster and still feel comfortable with the pace.
You just don't want you to feel you are pushing
it - feeling tired - as this increases the chances of pushing too hard and an
injury. So it really doesn't make any difference how fast you are going
(in fact you might actually do better if you just put some tape over your
speedometer and rode like you felt).
Q. Luke: "Can you please make me a base training schedule with a little bit of
pedaling/cadence drills inside it that I could follow, for about 10 weeks (or
more/less) to 500 miles? I'm trying my best to get a cyclocomputer with cadence,
as I want to have a great technique on pedaling as well as high cadence in
cycling."
A.Cadence, or revolutions per minute of the cranks, is a number that
deserves a few comments. Keeping a good cadence (I encourage 90 - 100 revolutions
per minute) will lessen the force delivered by your thigh muscles to the pedals of
your bike through the knee compared to a slower cadence for the same road speed.
Thus a higher cadence will decrease the chance of a knee injury.
Cadence and power output (work being done by your legs) are two different issues, so
even in this training base phase, riding at an easy PACE (lower work output),
it is good discipline to work on keeping your cadence in the 90 - 100 RPM range.
An example might help. I have found the calculators at
the
Analytic Cycling website to very helpful in sorting out questions such as this.
Assuming you use the basic assumptions suggested on this webpage, and you only change the cadence,
you get the following:
- 60 revolutions/minute = 260 units of force on the pedal
- 75 revolutions/minute = 208 units of force on the pedal
- 100 revolutions/minute = 156 units of force on the pedal
Thus maintaining the same road speed (work output) you will get significantly decreased
stress on the leg (and knees) riding at a higher cadence.
It will be tough to focus on cadence without a computer, but you can do it. And
once you get use to a faster cadence, you will begin to keep it more naturally without
thinking about it.
It will require concentration at first - and you may find yourself spinning at 65 or 70 as a
more natural rhythm for you. But remember, assuming a set pace, faster
cadence = less power to the knee per revolution = less stress on the knee joint,
=less chance of injury. And 90 - 100 RPM is your goal. (By the way, Lance Armstrong was
known for riding at a high cadence, often 120 - 130, and this set him apart from his peers
on the road.)
You've ridden your base miles, and it's time to ramp up the training program.
The next step, as we move forward, is to look at the goal you've set for yourself
(long distance ride - a century perhaps?, multi-day ride/tour, or competitive
event) as well as the types of
training rides you will be doing along the way.
This analysis will help us develop a rational training plan and a
sound nutrition program to support the effort. Our final plan should include:
- the weekly mileage goals
- the best use of intervals
- how you will utilize the basics of nutritional physiology to "eat
smart" and minimize the chances of "running out of gas" along the way.
Two aspects of each ride, length (duration) and intensity, will affect planning.
For example:
- Ride Length/Duration
- Goal ride length will determine total weekly training mileage and the
the distribution of mileage across weekday rides
- if any ride will be more than 2 hours (including training rides),
you will need to think about oral Caloric supplements.
- Ride Intensity
- if the goal ride involves riding at > 80% VO2max, intervals will be an
essential part of your weekly training program
- if you will be riding at > 80% VO2max, and will be on the bike for
more than 2 hours, you will definitely need carbohydrate supplements to
maintain internal muscle glycogen stores for what may become an
intermittently anaerobic effort.
The following 6 examples cover the most common training ride and
goal ride scenarios.
- THE COMMUTE or SOCIAL RIDE
- Duration - less than 2 hours
- Intensity - 50 - 60% VO2max
This ride is done at a comfortable pace of 50-60% VO2 max. for 1 to
2 hours, often multiple days of the week. The goal is a comfortable ride with energy left
for the remainder of the day.
- BASIC TRAINING RIDE (often referred to as LSD or long, slow distance)
- Duration - 2+ hours
- Intensity - 50 to 100% VO2max
- INTERVALS
- Duration - generally less than 2 hours
- Intensity - 80 to 100% VO2max
- LONG DISTANCE
- Duration - more than 2 hours
- Intensity - 60 to 80% VO2max
- COMPETITIVE EVENT
- Duration - 1 - 4 hours
- Intensity - 80 to 100% VO2max
- MULTI-DAY RIDE or BIKE TOUR
- Duration - multiday, 4 - 6 hours per day
- Intensity - 50 to 80% VO2max
Q. Hi there, currently I'm doing my base miles. I've got my cadence
computer already and training 90-110 rpm. But ... I don't have HRM, so how do I
know I'm doing the right intensity for base miles?
A. There is a two part answer to your question.
First, for this period of time you are putting in your base miles, you
should not be worrying about your riding intensity (except to avoid pushing
yourself and getting hurt in the process). It is okay to vary your riding,
do occasional sprints, but you should not be at a level of focus where a
HRM would be needed.
Then when we do get to outlining a training program, and want to
track your exertion, I prefer to use
perceived effort (exertion) -- often expressed
as %VO2max -- rather than a HRM to
track a level of exertion.
If you are interested in how your perception correlates with your
heart rate (without a HRM) and your %VO2max, you can get a good approximation by
- ride at a steady pace for 5 minutes or so
- estimate your level of exertion on a scale of 6 to 20
- then stop your bike and count your HR for 30 seconds.
- double this number and use this calculator
You now have a quick and easy correlation between perceived exertion, HR, and your
your personal %VO2max.
Let's work through a quick example. Your training program calls for a recovery
ride at 80% VO2max. This is actually a fairly reasonable pace so you want to
be sure you are not pushing your upper limits (which is the challenge of
these recovery rides).
- First, determine your MHR
(maximum heart rate). I prefer the real time approach,
on the bike or a trainer, rather than using your age. For purposes of this example,
let's say your personal MHR is 165 beats per minute (BPM).
- Using our calculator, 80% VO2max = 88.2% MHR.
We now know your target HR (165 x .882) = 146 beats per minute.
- The final step is to get on the bike and do a ride at a pace that you estimate
(perceived effort) is about 80% of your maximum. And
for the purposes of this example, you should quantify it. You are aiming for a
15 (a number than when multiplied x 10 would equal your heart rate).
- After riding for 30 minutes, stop the bike, count your pulse for 30 seconds,
and double it. If it is 145 +or- 5 BPM I think you are right on track.
This example demonstrates that a target heart rate of 146 (on a HRM), a perceived
effort of 15, and 80 %VO2max are all different ways of expressing a single level of
exertion.
VI. Training Physiology
There are a few key physiologic principles that we will use as we develop a
training program that is specific for you. I will highlight them here.
- No pain, no gain. I'm sure you have
heard this phrase many times at the gym or on the track. The concept of stress
leading to adaptive changes is the rationale behind all training programs.
A focused training program can increase your maximum performance by 15 to 30%
over a 3 month period and by up to 50% over 2 years. And the converse is true
as well, there is a drop off in performance and metabolic training adaptations
within a few weeks of stopping a regular training regimen, although certain
adaptive physical changes (such as the number of muscle capillaries and skeletal
and cardiac muscle fiber size) probably occur more slowly.
Regular exercise (walking, running, cycling, etc.) stimulates changes in the cardiovascular system, lungs, and muscle cells
which improve oxygen delivery and thus work capacity - for both endurance and
sprint activities. Oxygen is extracted from air in the lungs
and then transported in the blood to the cells where it is extracted and
utilized. The byproduct of energy production, carbon dioxide, is then
transported back to the lungs by the circulating blood and leaves the
body in expired air.
There are also improvements in the efficiency of energy production to support
high level performance:
- metabolic adaptations to facilitate aerobic energy production from glucose
and glycogen
- improvement in lactic acid removal from the muscle cell.
- an increase in lipid metabolism at any level of exertion which results
in extra energy Calories from fat to supplement those from glycogen and
glucose metabolism at any specified level of activity
And finally there are changes in the musculoskeletal system, changes in
the physical structure within the muscles and ligaments to withstand
the stresses of prolonged exertion including strengthening of the
connective tissue between muscle fibers to minimize the microtrauma (and post
exercise discomfort) that often occur with physical exertion.
These training related adaptations in the CV, metabolic, and musculoskeletal systems
will allow you to perform at a higher level for longer periods of time.
- VO2max or Maximal Oxygen Consumption
is defined as the maximum amount of oxygen that an exercising individual can utilize in
a predefined period of time (generally expressed as a volume i.e. liters per min).
It can also be normalized per kilogram of body weight (i.e. ml per kg BW per min).
It is a measurement reflecting the upper limit of aerobic muscle cell metabolism and
is a product of the maximal cardiac output (amount of blood being
circulated per minute by the heart)AND the maximal arterial-venous oxygen
difference at the muscle or tissue level (the amount of oxygen that can be
extracted from each ml of blood passing by the cell. It will increase
with training,
When we construct a training program, the %VO2max is used as a reflection of
the degree of exertion on a ride. Generally you will ride
at one of 3 levels.
- 100% VO2max - interval training
- 80% VO2 max - this level does lead to conditioning and improvement of
performance, but not as quickly as with intervals
- 50 - 60% VO2max - for recovery days and the longer ride of the week.
- aerobic vs anaerobic metabolism.
For the most efficient production of "usable" energy (by the muscles) from
the food we eat, oxygen is necessary. Oxygen is extracted by the lungs from
the air we breathe and then transported via the
cardiovascular system (bound to hemoglobin) to the cells where it will be
utilized. One of the end products of energy production, carbon dioxide, is then
transported back to the lungs and leaves the body in expired air.
When there is adequate oxygen to support energy production, metabolism is said
to be aerobic. When the
demand for energy at the cellular level outstrips the ability of the
cardiovascular system to provide adequate oxygen for oxidation, a more
inefficient form of metabolism, anaerobic metabolism, comes into play.
Training improves the level of exertion that can be maintained by aerobic
metabolism alone. And a structured program that includes "intervals" which stress
the muscles into an anaerobic zone, will increase the speed of this improvement.
VII. Two Components of a Successful Training Program
We are almost there, designing a training regimen for you.
- you have put in your 500 base miles
- you have given thought to your ultimate goal (both ride length/duration and
ride intensity/pace)
- we have reviewed the basic physiologic principles common to all training
programs
- and you can estimate your level of exertion while riding - from a leisurely
pace of a recovery ride at 50% VO2max to an all out anaerobic interval/sprint at 100% VO2max
To be successful in meeting your training goals, you will need two things.
- First is a traditional weekly program of rides to improve the performance
of your cardiovascular and musculoskeletal systems - the engine that drives the
wheels of your bike.
- The second, often overlooked, is a nutritional plan that
lets you take maximum advantage of your training. Nutrition is the fuel
for the work you will do. And you can have the most highly tuned cardiac and
respiratory systems in a pack of riders and yet lose the race as you run out
of fuel. A sound eating program will not magnify your advantage, but a failure
to eat properly will definitely limit the benefits of your training.
Failure to adequately replace fluid losses associated with exercise is the single
biggest contributor to poor performance in competitive athletes. This is
especially true in cycling where evaporative losses are significant (sweating
and loss through the lungs can easily exceed 2 quarts per hour).
To take advantage of your training program, and assure that you perform at your
personal best, it is essential that fluid replacement begin early and continue
throughout a ride.
A South African study comparing two groups of cyclists (one focusing on
staying hydrated, the other not) exercising at 90% of their personal maximums
demonstrated a measurable difference in physical performance as early as 15
minutes into the ride.
While riding you should be taking in a minimum of 4 to 5 ounces of fluid
every 15 minutes or 1 to 2 standard water bottles per hour. When extreme
conditions of heat and humidity are
anticipated, and the risks of dehydration are higher, the following strategy of
maximizing hydration before you start the activity can be a good preventative measure.
- drink 20 oz of cool water 2 hours before exercise
- 8 to 16 oz 30 minutes before
- and then 4 to 8 oz every 15 minutes on the bike
But a word of caution. With the frequent emphasis on "staying hydrated", the
pendulum on fluid replacement requirements can swing to the opposite extreme
where overcompensation, drinking excessive amounts of electrolyte free water (read
sodium or salt here), has occasionally led to an even more serious and life
threatening
condition - dilutional hyponatremia (low blood sodium
concentration).A recent study found that
overhydration with hyponatremia
was a far more frequent finding in runners who had collapsed than dehydration.
Here are several hydration tips:
- Hydrate before, during, and after the ride - force yourself to drink as thirst
alone will not reflect complete rehydration, so learn to drink before you are
thirsty. Using a CamelBak or similar device on long rides will eliminate worries
about stopping and possibly losing your group. Watch the color of your urine, if you are
doing a good job on replacement it should be colorless.
- Don't skimp when using a sports drink - don't assume that because they contain
electrolytes and carbohydrates you don't need to drink as much. As the sweet taste often
keeps you from drinking, dilute it or take an extra bottle of plain water to alternate.
- Keeping liquids cool has been shown to increase intake on a ride - either add
ice the day of the ride or freeze half a water bottle of fluid the night before and top
it off with water from the tap or extra sports drink just before the ride.
- Weigh yourself before and after the ride - most of your weight loss will be
fluid (2 pounds equals 1 quart or "a pint's a pound"). A drop of a pound or two
won't impair performance, but any more and you need to reassess your personal
hydration program. A gain of more than 1 or 2 pounds suggests you are over
compensating. This is an especially important strategy in hot weather where fluid
losses can easily exceed several quarts an hour.
- Wear the right clothing - light colored to reflect heat and a loose
weave jersey to help keep you cool and lessen sweat losses.
- Wear your helmet - modern well vented helmets funnel the wind onto your head
and are actually cooler than your bare head. And the helmet material will insulate
your head from the heat of the sun's rays.
We will cover the components of a traditional training program next, and then
move on to optimizing your nutrition.
IX. Your Training Schedule
Now that we have covered basic training principles, we will pull them
together into a rational training program for you. The basic unit of our training
program will be the training week. Seven days of riding and resting.
Each day on the bike has two components - ride length/duration and
ride intensity, the same two aspects I asked you to consider
in defining your season's riding
goals above.
Each week will consist of 5 days on the bike - 1 high mileage day,
1 slow recovery day, and 3 intermediate mileage days of variable intensity. The
other 2 days will be rest days - off the bike (or short recovery rides).
We'll cover the details (length, intensity) of each ride, and how they fit
together into a training week, in the next several sections. But first, a few comments
on "rest". One of the bigger risk an enthusiastic rider faces is overtraining,
right after pushing too many miles and developing a physical injury (the
reason one has to be disciplined and put in those base
miles before starting to push oneself.
Fatigue, the tiredness one feels after riding, is a normal part of
the training process. It is to be expected after the physiologic over load of
exercise and is a natural response to the stimulus which leads to adaptation and
performance improvement. Fatigue is our signal that we are pushing our physical
limits. However, in certain circumstances, fatigue can be a warning that we
are pushing too hard (that there is an imbalance between
exercise and recovery), and indicate the need to back off or risk an actual
deterioration in our performance. This is a common dilemma in a personal
training program: Hard work makes us faster, but how much is too much?
One of 5 types of fatigue, overtraining is the
result of " doing too much, too quickly". The body responds well to regular, moderate
changes, not upheaval, in a training program. So the rationale for rest days, recovery
days on the bike, and limiting mileage increases to no more than 10% per week, is to
minimize the risk of overtraining and the debilitating
and often long term (weeks to months) fatigue which limits rather than stimulates
improvement in performance.
The most important aspect of preventing overtraining is realizing you are
almost there. A good training diary is
a tool you can use to alert
yourself to this risk. In addition to the usual training facts such as mileage and
times, it should include a daily notation on:
- resting heart rate before getting out of bed
- mood self assessment
- self assessment of level of fatigue throughout the prior day ("heavy legs")
- minor illnesses - i.e. GI upset, diarrhea, sore throat, and runny nose
- performance (time) on a weekly standardized ride done at your perceived maximum. More
scientific would be measurement of oxygen consumption (down), heart rate (up), and blood
lactate levels (down).
Next, more about the 3 types of training rides - high mileage days,
slow recovery days, and the intermediate mileage days of variable intensity.
X. Your Training Week
First step, calculate your average weekly mileage for your last 2 or
3 weeks of riding. This will give you the mileage of your first week - then,
to minimize injuries, you should increase your weekly mileage by
no more than 10 to 15% per week. Here is an example of the
process - Example.
You can also estimate the length of a training program to
reach a personal goal by
using the average long ride from your 500 mile base training period,
increasing it by 10 - 15% a week, and repeating this until you arrive at a figure that is
equal to or greater than 75% (3/4) of the length of the event for which you are training.
The number of repetitions needed to get to the 75 % number is the number of weeks
of your training program. See Step 2 in the example.
How should your mileage be divided throughout the
week? It will require balancing frequency, intensity, and duration of the
individual rides to achieve your personal goal. For more detail, review
this summary of training techniques.
Here is how I balance the three.
It's important to ride at least 5 days a week, and take at least one day
off.
- One high mileage day - working up your mileage by 10 to 15% per week until it
equals your event distance
- The longest mileage day is keyed to the length of your event or ride and ridden at
the pace you hope to maintain for the event. Many coaches suggest you work up to the
length (or even 125% of the length) of the event while others are comfortable if you
can ride 75% of the event distance comfortably.
- This is usually a Saturday ride, with Sunday as a backup for bad weather or other
unexpected circumstance that might derail your training program.
- The last high mileage day of your training program should be at least 75% of the
length of the planned event.
- If you are training for a single day event or ride, your longest training ride should
be at least 10 to 14 days before the event. Cut back on the mileage of your rides
3 days before the event, substituting short, low intensity rides (spinning) to keep
your muscles from tightening up. This recommendation is not as important for multiday
endurance type rides, but common sense suggests that taking a few days off (short
spinning rides only) immediately before an event will facilitate maximum muscle recovery
and glycogen repletion.
- Follow the high mileage day with a rest day (or if you prefer, a 6th
riding day - at most 1/4 of the length of your long ride and ridden at a leisurely pace to
help loosen up your muscles after the long ride of the week).
- Three intermediate mileage days
- The three intermediate mileage (midway between the short ride and the long ride of
the week) days should be ridden at a good training pace (85 to 90% of your
maximum heart rate). At least one should be an
interval training ride. A second interval training day each
week is optional.
- One slow recovery day - longer than the intermediate mileage days, shorter than
the high mileage day.
- One or two rest days - off the bike or short recovery rides. Depending on your level
of training (or evidence of overtraining) the seventh day is an additional intermediate
mileage day or an additional rest day.
Be flexible and adjust your program to your lifestyle. A rigid program is destined
to fail.
Intensity
As far as pace of your rides:
- the pace of the longest ride of the week should match the planned pace of your
event
- the short "recovery" ride should be a leisurely pace at no more than 50-60% of
your maximum heart rate
- two of the intermediate rides should be at the planned event pace
- one of the intermediate rides (preferably prior to a planned day off the bike for
a 5 day training week), should be at a brisk pace 2 - 3 mph faster than your planned
event speed.
XI. Nutrition Basics
You may have the best training program in the world and have developed the
optimum "engine" for your cycling event, but if you don't eat right, that is
provide the optimum "fuel", you will not ride at your best.
How should one eat to get the most out of their training program?
There is a two part answer.
- First, which type of Calorie (carbohydrate, fat,
or protein) is best to support the exercising muscle?
- Second, what are
the effects of exercise on the digestive tract, important in deciding what and
when you should eat to get those Calories into your system.
I. Type of Calorie - carbohydrate, fat, or protein
Carbohydrates which contain 4.1 Calories per gram (120 Calories per ounce)
are the preferred fuel for muscle metabolism.
- Carbohydrates are stored as glycogen in the liver and muscle cells -
your body contains about 1500 Calories of glycogen (enough for 2 hours of exercise
if you eat nothing at all)
- The carbohydrates you eat are either simple 6 carbon sugars such as glucose
or complex (composed of multiple 6 carbon units). Complex carbs are digested
and enter the circulatory system more slowly.
- Caloric value of CHO depends to a degree on whether one is exercising aerobically
or anaerobically. This is where the concept of VO2 max comes in. Above 100%VO2 max,
you no longer have enough oxygen to support efficient use of food energy.
For example, carbohydrate metabolism will produce 19 times as much energy per
gram when carbohydrates are metabolized in the presence of adequate cell oxygen
supplies (aerobic) as opposed to its metabolism in an oxygen deficient
(anaerobic) environment.
Fats contain 9 Cal/gram.
- The disadvantage of fat as a fuel for exercise is the fact that fat is
metabolized through pathways that differ from carbohydrates and alone can
support an exercise level approximately 50% VO2 max. at most. As performance
levels increase, the percentage of Calories provided by fat decreases.
- Even the leanest athlete has plenty of stored fat available
(approximately 100,000 Calories worth in a 70 kg male)
- They play only a minor role in short distance, maximum performance events
at 90 to 100% VO2 max.
- Fat Calories are fine for lower work intensity which makes fat the ideal
fuel for endurance events. They are a particularly important energy source
for the endurance cyclist.
Protein is only used as an energy source in malnourished states.
(see NUTRITION FOR TRAINING AND PERFORMANCE for a more detailed
discussion).
The Bonk
When the body's 1500 stored carbohydrate Calories are gone, only fats are left
(plus any carbs you eat) At that point, the exercise level drops to 50% VO2 max.
at most as there is only fat to provide your exercise Calories. One can avoid the bonk by:
- supplementing stored carbohydrates with eaten carbohydrates
- exercising at lower levels of exertion (lower VO2) where less CHO is being
used to provide Calories for exercise. Thus slowing the pace increases the % of energy derived from fat and can extend carbohydrate reserves.
II. Effects of exercise on digestion (getting what you eat into your system and to the muscles).
Before we go any further, let's take a minute to discuss the role of the various
parts of your digestive tract.
- Mouth - important to begin the mechanical breakdown of food and add some digestive enzymes in saliva
- Esophagus - transportation to the stomach
- Stomach - further mechanical and enzyme breakdown; no absorption
- Small intestine - completes enzyme breakdown and absorption into the blood with transport to the muscle cell
- Colon - storage and dehydration of already processed food; no absorption
When designing a nutritional program to supplement your body's 1500 stored Calories for
an athletic event, the rate of digestion and absorption of foods must be taken
into account. The time needed for:
- the stomach to start the digestive process
- empty its contents into the small intestine
- and have the food components absorbed into the bloodstream
will directly affect how quickly any food will be available to the muscle to
provide the supplemental Calories for exercise.
Emptying of the stomach into the small intestine is the rate limiting step in
getting Calories into the blood stream and to the working muscles. Once
food molecules get into the small intestine, they are absorbed quite quickly.
You have control over the four major factors that can delay stomach emptying.
- Solid versus liquid - liquids are emptied from the stomach more quickly than solids.
- Fat content of the food - fat slows the digestive process and delays the availability of any Calories in the food to the muscles.
- Sugar concentration - especially in liquids, a sugar content of more than 10% will slow stomach emptying. ( The use of complex carbohydrates, due to the decreased osmotic effect, will offset this to some degree and offers an alternative strategy to maximize Caloric intake to offset the metabolic needs of exercise.)
- Physical activity level of the cyclist - the mechanical activity of digestion is slowed by any vigorous activity, usually starting at 70% VO2 max. Except in short, all out events, this is rarely an issue, and it is much less so for cycling than for running where the additional component of mechanical stimulation of abdominal contents from the sport itself slows digestive tract functioning.
The bottom line? The optimal food for
a rapid, high-energy boost during a ride would be a semi-liquid or liquid
carbohydrate with minimal if any fat. On the other hand, an endurance athlete,
competing at a lower VO2 max., might prefer a complex carbohydrate with some
fat added to improve taste (and generally in a solid form), in order to slow
emptying from the stomach and even out absorption over a longer period of time.
.....more to come. Send any feedback via the
CPTIPS Facebook page or
directly to me at cptipsnew@gmail.com
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Cycling Performance Tips
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