Beta Alanine Supplementation

July 7, 2010

If you pick up any fitness magazine or walk into any nutrition store you will find dozens of products that claim to improve performance, with more showing up on the store shelves every month. In most cases the claims are exaggerated with very few products actually improving performance. Every now and then however a product does come along that lives up to the hype; about twenty years ago that product was creatine, which has gone on to become the most researched performance enhancing supplement with the vast majority of studies supporting it’s use in most athlete groups.  Recently another product has started to show that same type of promise: Beta alanine. Beat alanine supplementation has been reported to decrease fatigue associated with higher intensity exercise.

Fatigue during Exercise

Fatigue, defined as the inability to carry on a given level of work, is a complex phenomenon with many factors contributing simultaneously. While the inability of the nervous system to activate muscle fibres, interference with calcium release or uptake within the muscle, structural damage to muscle fibres, heat, and depletion of energy stores are some of the main culprits, an accumulation of metabolites like ADP, inorganic phosphate,  lactate and hydrogen ions are among the most well known contributors to fatigue.

There has been an ongoing debate about the role of lactate in fatigue. Research conducted in the 1970s suggested that lactate was a major contributor to fatigue. Many of these studies were correlation studies that did not look at cause and effect. While there was a correlation between the amount of lactate that was produced and fatigue more recent research has shown that lactate itself does not contribute to fatigue and may actually work to prevent fatigue. The production of hydrogen ions, from various sources in the series of chemical reactions that take place when the anaerobic energy systems are used, can lead to a decrease in the pH of the cell; interfering with energy production and muscle contraction.

Buffers

Buffers are the body’s chemical agents that keep pH in the cells within normal range. There are a variety of buffers that the body uses. Bicarbonate is the most important extracellular buffer, meaning that it maintains the pH outside of the cells. It has been known for many years that ingesting sodium bicarbonate, baking soda, can increase the effectiveness of the bicarbonate buffering system in the body and delay fatigue in high intensity sports. For many people ingesting baking soda causes stomach problems and can lead to vomiting or diarrhoea, unpleasant side effects at the best of times but particularly problematic during competition.  Carnosine is the primary intramuscular buffer found in humans, it also seems to have positive effects on the nervous system, acts as an antioxidant and may have anti aging effects.  Carnosine does not appear to be increased by exercise  but supplementation with Beta Alanine does increase intramuscular carnosine and improve buffer capacity.

Effects on Performance

The majority of studies suggest that beta alanine can enhance performance in sports where there are maximal or near maximal efforts for 60s to 5 minutes. Shorter duration sprints and strength training do not seem to benefit as much from beta alanine use, although total work volume in strength training sessions can be improved by as much as 20% following beta alanine supplementation. Whether the increase in work volume can translate into better training adaptations and performance improvements is not known. Two studies have shown improvements in power at anaerobic threshold following beta alanine supplementation and slight improvements (2.5%) in time to exhaustion at anaerobic threshold.

Supplementation Protocol

Several studies have been done on to find the optimal protocol for taking beat alanine. It appears that ability of beta alanine to increase carnosine is dose dependant, 6-7 g per day give best results. Beta alanine supplements often cause tingling sensations in various parts of the body, particularly in the head and neck region. This can become quite intense and unpleasant if large doses are taken at one time. The tingling can start within minutes of taking the supplement and last for up to an hour.  Smaller doses spread throughout the day or time release capsules seem to decrease or eliminate the tingling. Beta alanine supplementation is not an acute response supplement it needs to be done over an extended period of time for significant effects to be noticed, usually 28 days or more.

Adverse Effects

Currently the only known adverse effects associated with beta alanine supplementation is the tingling that is noticed shortly after taking the supplement.

References

  1. Allen DG, Lamb GD, Westerblad H. Skeletal muscle fatigue: cellular mechanisms. Physiol Rev. 2008;88(1):287–332.
  2. ARTIOLI, G. G., B. GUALANO, A. SMITH, J. STOUT, and A. H. LANCHA, JR. Role of A-Alanine Supplementation on Muscle Carnosine and Exercise Performance. Med. Sci. Sports Exerc., Vol. 42, No. 6, pp. 1162–1173, 2010
  3. Boning D, Maassen N. Last word on point:counterpoint: lactic acid is/is not the only physicochemical contributor to the acidosis of exercise. J Appl Physiol. 2008;105(1):368.
  4. Cairns SP. Lactic acid and exercise performance: culprit or friend? Sports Med. 2006;36(4):279–91.

Breathing Stronger

July 1, 2010

The regular use of strength training has been slow to catch on with endurance athletes. While there is evidence that strength training decreases both acute and chronic injury in these athletes, and improves running and cycling efficiency by 3-8% many endurance athletes simply do not enjoy lifting weights. This may be due in part to what is being trained. Traditional programs focus on the major muscles of the legs, hips, back, and shoulders of endurance athletes. A new trend has emerged in recent years that includes the training of the muscles used in breathing.

Breathing is something we take for granted.  We don’t think about the work that goes on every time we breathe, either at rest or during normal daily activity. During very intense exercise, like that experienced during interval training or racing, up to 15% of the energy produced is consumed by respiratory muscles. This is energy not used to make the athlete go faster and can put a pretty big dent in your body’s carbohydrate stores, requiring more fueling during the event.

There are several respiratory training devices on the market designed to improve the strength and efficiency of the inspiratory musculature, those muscles that allow us to inhale. This is done by increasing airflow resistance through a special valve.

A study from Great Britain examined the effects of 11 weeks of inspiratory muscle training on rowing performance as measured by a 6-minute all-out test and a 5000 m test both on the Concept II rowing ergometer. Fourteen female competitive rowers (All-British National Team candidates) participated in the study. They were broken into two groups. The first, trained twice a day using 30 breaths per session at a resistance equal to 50% of the maximum inspiratory pressure they could generate (inspiratory pressure is the maximum pressure that can be generated when breathing in). The second group, a placebo group, trained once a day, 60 breaths with 15% of maximum inspiratory pressure, a training protocol that does not significantly increase inspiratory muscle strength. The athletes were tested at the start of the study, at four weeks, and again at the end of the study.

The training group improved their 6-minute test performance by 3.4% after four weeks of breathing training while the placebo group only increased by 1.1%. By the end of the 11 weeks the training group had improved by 3.5% and the placebo group had improved by 1.6%. The researchers suggest that the difference of 1.9% improvement between the two groups is the result of the inspiratory muscle training.

In addition, the training group improved their 5000 m test time by an average of 36 seconds, while the placebo group improved by only 11 seconds. These results were brought about by a 41% improvement in respiratory muscle function for the training group and 5% for the placebo group, as measured by an increase in maximal inspiratory pressure.

While a 1.9% net improvement doesn’t seem like a lot, many races are won or lost by much less than 1.9%. This is equal to almost seven seconds over a 2000 m course. One of the interesting things to come out of this study was that almost all of the performance improvements came in the first four weeks of the eight week training program. This may be due to the fact that the resistance was self-adjusted during the study and not subject to a periodized plan.

While respiratory muscle training does not solve all an endurance athlete’s performance problems, the results of this study clearly suggest that a high level athlete may benefit from respiratory muscle training. Whether these results can be applied to athletes with lower fitness levels remains to be seen.  Additionally, there is still a lot of work to do to find the most effective training program for these muscles.

The main mistake that people make when using inspiratory muscle training devices is that they try to train while using the device. This is nearly impossible if the device is set up properly. These machines are meant to increase the resistance to airflow coming into the lungs. It is like lifting weights for your diaphragm and other breathing muscles; you wouldn’t try to do squats while riding your bike would you? Set up a training session using sets and reps just like weight training. Start with 3-4 sets of 8-10 reps, gradually increase the resistance on the inspiratory trainer over a period of 4-8 weeks.

Inspiratory muscle training is not going to suddenly cause huge changes in your race performances but it is one of the small things that you can do without a lot of cost or effort.  If you do enough small things they can all add up to big performance improvements.

(As a side note, personal communication with rowing coaches from Britain and Australia revealed that at least two medal winning boats from the Sydney Olympics included inspiratory muscle training as part of their preparation for the Games.)

References

Voliantis, S., McConnell, A., Koutedakis, Y., McNaughton, L., Backx, K., and Jones, D. (2001). Inspiratory muscle training improves rowing performance. Medicine and Science in Sport and Exercise. 33(5) pp 803-809.


Warm Up

June 22, 2010

Warm up is now considered an essential part of a workout or pre competition routine. While originally thought to be primarily a means of preventing injury, it is now commonly accepted that the main purpose of warm up is to improve performance with injury prevention taking a secondary role. The positive effects of warm up occur because of several mechanisms; increased muscle temperature, cardiac adaptations, injury prevention and mental rehearsal.

Increased Muscle Temperature

An increase in body temperature is one of the main physiological adaptations to warming up.  The increase results from unused energy and dissipated heat produced by friction from sliding muscle filaments during contraction. The elevated temperature results in a more rapid and complete dissociation of oxygen from hemoglobin enhancing oxidative processes in the muscle and increasing VO2 max. Increased body temperature stimulates vasodilation in the working muscle increasing blood flow through the muscle and reduced muscle viscosity increasing mechanical efficiency. Nerve conduction velocity is improved resulting in faster contractions and relaxation of muscles. The heart rate increases and lactic acid production decreases after warming up.  All these changes add up to improved performance following warm up.

Cardiac Adaptations

Heart problems such as myocardial ischemia, arrythmias, and sudden cardiac death can occur during exercise. These problems tend to occur most often in middle-aged and older men. When exercise is combined with other coronary risk factors such as hypertension, cigarette smoking, obesity, and high cholesterol the risk of exercise related cardiac problems increases.

Warming up, however, may help prevent serious damage to the heart. In one study it was reported that 68% of their subjects, men aged 21 to 52, experienced abnormal ECG readings when they exercised without warming up. Jogging easily for two minutes before the training session though eliminated the abnormal ECG readings in most subjects and reduced it in the others. Abnormal readings seen during training without a warm up have been attributed to the inability of coronary blood flow to meet the demands that the exercise session places on the heart muscle.

Injury Prevention

Preventing injuries, such as muscle strains and tears, is often suggested as one of the primary benefits of warm up. Even though most coaches suggest that warming up can help prevent injuries most of the evidence is empirical and that very few, if any, studies can show that warming up decreases the incidence of musculoskeletal injuries. This is in part because during a study a researcher would never set out to injure their subjects intentionally. It is hypothesized that warming up can help prevent injuries because it stretches the muscle tendon unit resulting in a greater length for a given load; this places less tension on the muscle-tendon junction reducing the potential for injury. However, the majority of musculoskeletal injuries occur because of strength or flexibility imbalances and therefore not affected by warm up.

Mental Rehearsal

Warm up provides an athlete the time to mentally review and prepare for the training session of competition that follows. Visualizing the activities to follow increases nervous system arousal, increasing the number of motor units activated, improving strength and power activities and enhancing skill acquisition.

Types of warm ups

There are three types of warm ups: passive, general and specific. Each has its advantages and disadvantages.

Passive warm up

A passive warm up increases temperature through external means. Massage, hot showers, lotions, and heating pads are common forms. Although these methods increase body temperature, they produce little positive effect on performance. Several researchers have compared the effects of active, passive and no warm up on physiological markers of performance. They found that the passive warm up did not increase VO2, or decrease blood lactate levels any more than no warm up. They did find though that the heart rate increased. A passive warm up, because of increased muscle temperature, may be suitable prior to a stretching exercise but should not be recommended as the sole means of warming up for intense physical activity.

General Warm Up

A general warm up increases temperature by using movements for the major muscle groups. Calisthenics and light jogging activities are most common. This type of warm up is meant to increase temperature in a variety of muscles using general movement patterns. This is a good warm up for a fitness class but should not serve as the sole form of warm up for athletic training or events.

Specific Warm Up

The specific warm up is designed to prepare the participant for the specific demands of the upcoming activity. The specific warm up helps psychological readiness, co-ordination of specific movement patterns, and prepares the central nervous system. A specific warm up usually consists of a simulation of some technical component of the activity at work rates that increase progressively. For example, an Olympic weightlifter will perform the snatch with heavier weights progressively until reaching 80-90% of the opening attempt. Because of the rehearsal component of this type of warm, it is the preferred method for sports activities, particularly high speed and power activities.

Designing a warm up

A good warm up has both a general and specific component and may include a passive component if the athlete feels they perform better when they use some sort of a topical analgesic like Tiger Balm.

General Warm Up

Full body Calisthenics

A warm up starts with some full body calisthenics. Exercises like jumping jacks, rope jumping, push ups, sit ups, and lunges are full body exercises that will increase body temperature. These exercises should be done for only 1- 2 minutes at a time as the goal of warm up is to increase temperature not create fatigue.

Stretching

Dynamic stretching is a more effective means of warm up stretching than static stretching, meaning that rather than holding a stretch for a period of time you move through a full range of motion and then back to your starting position immediately without holding the stretch. This is particularly true when you are doing power training. Several studies have shown that a static stretch immediately before power training can significantly decrease subsequent power development. This is because the static stretch decreases the effectiveness of the stretch shortening cycle.

Duration of General Warm Up

The amount of time needed to warm up depends on the type and intensity of the activity as well as environmental conditions. For someone engaged in a light jogging program 10 minutes may be sufficient for a warm up. Elite level athletes may require 30 or 40 minutes to warm up depending on the nature of the event, with higher intensity events requiring longer warm ups. Exercising in a warm environment requires a shorter warm up than exercising in a cold one. In a normal environment the onset of sweating is usually a good indicator that body temperature has increased sufficiently.

Specific Warm Up

The nature of the specific warm up depends on the activity to follow. Keep in mind that warm up is just that warm up not training, fatigue should be kept to a minimum during warm up otherwise the training session will suffer.

Warming Up for Strength Training

When weight training, do at least two sets, one at 50% and one at 75% of the work weight, before using the working weight. Very strong people need to do more sets. Many elite powerlifters and weightlifters use six to eight warm up sets prior to opening attempts in competition. Repetitions in warm up sets are low, 1-4, and done at a controlled speed. Warm up sets are done for every exercise in the program, not just the first exercise.

Warming Up for Speed, Agility and Power Training

As in weight training a warm up for speed, agility and power events or training uses warm up sets. Prior to each drill start with a walk through set that allows you to rehearse the drill in your mind and remind you of the movements and changes of direction that have to be made. Following the walk through perform two progressively faster trials, one at about half speed and one at three quarter speed. Be sure to focus on good technique during each of the warm up sets, the way you perform in warm up will be the way you perform in the training session.

Warming Up for Aerobic Training

Since most of the aerobic training you will be doing is low intensity there isn’t a specific portion to the warm up. If you were to do higher intensity aerobic intervals you would start with 10 –15 minutes of light jogging prior to starting the interval portion on the session.

A good warm up can make the difference between an adequate and a personal best performance. If you are having trouble int eh early parts of an event or seem to get a second wind take a look at your warm up it may need some fine tuning.


VO2 max and Cyclists: Important or Irrelevant

June 16, 2010

VO2 max is one of the most commonly measured physiological variables. Endurance athletes spend countless hours discussing, comparing and worrying about their VO2 max scores. Cyclists are always quoting VO2 max scores for one top rider or another. Is all the attention that this physiological variable gets really worth all the effort?

VO2 max is the maximum amount of oxygen that your body can take in and use. It is a function of both the body’s ability to deliver oxygen via the heart, lung and blood and the body’s ability to use oxygen in the working muscles and other tissues.  While there are some exceptions, Elite cyclists typically have VO2 max scores in the 70-75 ml/kg/min range, similar to that seen in well trained amateur cyclists and some very fit age group riders. In an aerobic sport oxygen consumption is tightly tied to energy expenditure and generally producing more energy means more power and work. The relationship between power and oxygen consumption is not perfect; efficiency or economy play an important role in determining how strong the relationship is in each person.

Gross efficiency, the ratio of power output to power input, is a key determinant of cycling performance (1).  A higher efficiency allows a cyclist to work at lower percentages of the VO2 max to accomplish the same or more work as a less efficient cyclist. In fact, a high efficiency rating can make up for lower VO2 max scores. Alejandro Lucia and coworkers (2) from the Universidad Europea de Madrid examined the relationship between VO2 max and cycling efficiency and gross efficiency in a group of elite cyclists. The subjects in this study were all world class riders having won at least one major professional race, defined as stage in the Tour de France, Giro d’Italia or the Vuelta a Espana, or finished in the top three at the World Championships. Hemoglobin and hematocrit levels were measured prior to the start of the study to ensure they were within normal physiological ranges.  All subjects performed a VO2 max test following standard protocols.  Later the same day they performed a 20 minute constant load test where they road at 80% of their VO2 max. VO2 max values in the subjects varied from a high of 82.5 ml/kg/min to a low of 65.5 ml/kg/min. Cycling efficiency varied from 97.9 watts/L O2/min to 72.1 watts/L O2/min. There was a significant inverse correlation between VO2 max and cycling efficiency. This means that those with the higher VO2 max scores had the lowest efficiencies and those with lower VO2 max scores had higher efficiency. A similar pattern was seen in gross efficiency. Power to weight ratio at VO2 max was not significantly different between riders, they were all in the 4.9-5.4 W/kg range. Interestingly two of the most accomplished riders, a road race and time trial world champion and climbing specialist who had won five stages in the Tour de France both had VO2 max score under 70 ml/kg/min.

This study clearly shows that VO2 max is less important than efficiency in cycling performance and that a high level of efficiency can make up for a lower VO2 max. This pattern is not unique to cycling it has also been seen in running (3) and rowing. In an upcoming article we will look at the various factors that contribute to efficiency and how to improve your cycling efficiency.

So the next time someone start bragging about their VO2 max score ask them about their efficiency rating. Their high VO2 max may just mean that they are very inefficient riders.

  1. Coyle, E. (1995). Integration of the physiological factors determining endurance performance ability. Exerc Sport Sci rev. 23: 25-64.
  2. Lucia, A.  et al. (2002). Inverse relationship between VO2 max and economy/efficiency in world class cyclists. Med Sci Sports Exerc. 34: 2079-2084.
  3. Saltin et al. (1995). Morphology, enzyme activities, and buffer capacity of Kenyan and Scandinavian runners. Scand J. Med Sci Sports. 5: 222-230.