Journal

Scientific Studies

In this section I will provide a list of Scientific Journal articles which I have found to be informative. In addition tot hat I will try and give my opinion on what the study means in terms or real world application to training.
If you know of any journal articles that you think would be helpful to others, please e-mail(sjm1368@yahoo.com) the link to me and I will post them.

Psychological effects of EPO use:

Effects of recombinant human erythropoietin injections on physical self in endurance athletes. Ninot, Gregory; Connes, Philippe; Caillaud, Corrine

http://galenet.galegroup.com/servlet/SRC?ste=200&docNum=A143919841&locID=txshracd2542

Abstract

This study examined the time course of mean self-esteem and physical self scores in three groups: male endurance athletes treated with recombinant human erythropoietin (rHuEPO group, n = 6), a placebo group (n = 5) injected with a sodium chloride solution and a control group who did not receive any injection (n = 6). Each participant completed the Physical Self Inventory twice a day (between 07.00 and 09.00 h and between 19.00 and 21.00 h). Using a 10 cm visual analog scale, the participants assessed global self-esteem, physical self-worth and the sub-domains of physical condition, sport competence, attractive body and physical strength (Fox & Corbin, 1989). This was conducted over three consecutive periods: in the 2 weeks before the course of injections, during the 6 weeks of injections and for 4 weeks after the injections. Aerobic capacity was assessed before and after 4 weeks of treatment. The results showed a significant increase in aerobic physical fitness in the rHuEPO group and a significant increase in perceived physical condition and physical strength scores at the end of treatment. The main psychological result was that endurance athletes were highly sensitive to the effects of rHuEPO on physical fitness. The perception of increased physical condition may lead to a stronger commitment to training. The rHuEPO injections presented a dangerous hedonic effect linked to endurance training. These results confirm the need to tackle rHuEPO abuse at any time during the training season

My take: EPO use not only increases aerobic capacity, but it gives a psychological boost to the athlete when he is taking it, allowing him to train harder. In addition to this, the conclusion the authors made that "recombinant human erythropoietin may have reduced physical pain or the perceived effort invested in training," is interesting. That's interesting because in addition to the physical benefits of EPO, the idea of less percieved effort could limit the chance of psychological burnout or staleness. It would allow the athlete to do more work without becoming mentally tired.

Kenyan Runners

Journal of Sports Sciences April 2006 v24 i4 p415(8)

Demographic characteristics of elite Kenyan endurance runners. Onywera, Vincent O.; Scott, Robert A.; Boit, Michael K.; Pitsiladis, Yannis P.

http://galenet.galegroup.com/servlet/SRC?ste=200&docNum=A143919844&locID=txshracd2542

Abstract

Kenyan athletes have dominated international distance running in recent years. Explanations for their success include favourable physiological characteristics, which could include favourable genetic endowment, and advantageous environmental conditions. The aim of this study was to compare the demographic characteristics of elite Kenyan runners with those of the general Kenyan population. Questionnaires, administered to 404 elite Kenyan runners specializing in distances ranging from the 800 m to the marathon and 87 Kenyan controls, obtained information on place of birth, language, and distance and method of travel to school. Athletes were separated into two groups according to athletic success: those who competed in international competition and those who competed in national competition. The athletes differed from controls in regional distribution, language, and distance and method of travel to school; athletes also differed from each other with the exception of method of travel to school. Most national and international athletes came from the Rift Valley province (controls 20%, national athletes 65%, international athletes 81%), belonged to the Kalenjin ethnic group (controls 8%, national athletes 49%, international athletes 76%) and Nandi sub-tribe (controls 5%, national athletes 25%, international athletes 44%), and spoke languages of Nilotic origin (controls 21%, national athletes 60%, international athletes 79%). A higher proportion of all athletes ran to school each day (controls 22%, national athletes 73%, international athletes 81%) and covered greater distances. In conclusion, Kenyan runners are from a distinctive environmental background in terms of geographical distribution, ethnicity and travelled further to school, mostly by running. These findings highlight the importance of environmental and social factors in the success of Kenyan runners.

It has previously been shown that Kenyan boys who travelled to school by walking and running had a 30% higher [[VO.sub.2max] than those who did not (Saltin et al., 1995)

My Take: The majority of great runners come from a specific region of Kenya for some reason. This could be because of the high altitude in this region. In addition to this, a larger percentage came from select tribes. This shows that the Kenyan runners are coming from a distinct group in a distinct environment for the most part. The most striking finding is that of those who ran to school, only 22% of controls did, while 73% national athletes and 81% of international athletes ran to school. This gives some credence to the old tale of kenyans being good because they run to school from a young age. Also control groups tended to walk or use another method, instead of run to school even if they had to travel similar distances. Approximately 50% of international runner traveled over 5k to school. One more interesting thing is that out of the International athletes, 33% were motivated by economic reasons, 18% by talent, 18 % by tradition, 14% by olympic tradition, 7% by fun.
The study does not give any definitive answers to the success of Kenyan runners, but it does bring up some interesting questions. The fact that the amount of runners who run to school as composed to "normal" Kenyan citizens is very interesting. In my opinion, a difference of almost 60% doesn't just happen by chance. It strongly suggests that while it may not be a direct requirement to be an elite runner, running to school must help. It could give those athletes a good aerobic base like many have suggested. Also, the reasons to run is interesting.

Dudley, Abrahman, Terjung. Influence of exercise intensity and duration on biochmecial adaptations in skeletal muscle, Journal of Applied Physiology, 1982

Interpreted: In this study rats were subjected to 6 weeks of training for various intensities (from about 60% VO2max-116% VO2max) and different volumes (from 5min. to 90 min.). They divided the rats into 6 different intensity groups based on the speeds mentioned above, and then further divided each of these intensity groups into three volume groups. So for example at the 80% Vo2max speed, you'd have rats in a 30min, 60min, and 90min continuous run group. The rats then trained at these levels for 5 days a week for 6 weeks, after an initial 2 week training period to let the rats get used to training. After the training was completed, three different muscle fiber types were evaluated (Fast twitch red and white, and slow twitch red fibers) for cytochrome C concentration, which varies directly with mitochondria content. Although the study was with rats, the results give an idea of what intensities and volumes recruit the various muscle fibers to increase mitochondria content. I'll point out a few of the more interesting findings. In the Red Vastus fibers (roughly equivelant to FT-A fibers), the group that trained at an intensity of approximately 83%Vo2max produced the most change in cytochrome C concentration. After that the groups that trained at higher %Vo2max showed only the same level of increase or less. So from this it can be inferred that at an intensity of around 80% Vo2max, or around LT, the FT-A fibers are recruited almost fully and this is the least amount of effort to get the best results in these fibers. Also it should be noted that there was a dramatic increase in cytochrome C concentration between the group that trained 30 minutes to 60 minutes, and only a very slight increase from the 60 to 90 minute group. In the Soleus muscle (Slow twitch) the max increase in cytochrome C concentration also occured with the 83% group and it also occured in the 60 minute group, with no further improvement in the 90 minute group. The lower intensities also produced significant adaptation but not quiet to the same extent as that of the 83% group. What's interesting is that in the groups that performed work at 100% VO2max or better, not as much cytochrome C concentration increase took place. This could be explained by several things, including because of the increased intensity of the effort the duration at that effort per day was much less or that the acidosis that corresponds with this intense running somewhat blocked aerobic adaptations in the muscle. In the White Vastus fiber (FT-B), there was very little to no increase at lower intensities, and only a slight increase at speeds from 94-103% VO2max. However the group that spent 10min at 116% VO2max per day in the form of intervals showed a major increase. This shows that very fast speeds may be required to stimulate these fibers.

Intermittent runs at the velocity associated with maximal oxygen uptake enables subjects to remain at maximal oxygen uptake for a longer time than intense but submaximal runs.
Effects of High-intensity Training on Performance and Physiology of Endurance Athletes. Carl Paton and Will Hopkins.

Good summary on the effects of different kinds of training from V02max work , anaerobic work, to plyometrics and strength training.

Passive versus active recovery during high-intensity intermittent exercises.

Article discussing the differences between active rest and standing rest during interval work.

Effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO2max.

Study that shows the benefit of anaerobic training

Metabolic profile of high intensity intermittent exercises.

Study that shows the effects of Lactate Tolerance and Anaerobic Capacity training

Effect of recovery modality on 4-hour repeated treadmill running performance and changes in physiological variables.

Study that shows the benefits of cooling down and ice baths in clearing

The distribution of rest periods affects performance and adaptations of energy metabolism induced by high-intensity training in human muscle.

Article showing that too much High Intensity work does not allow muscles to recover and performance does not increase.

Influence of water run training on the maintenance of aerobic performance.

Study that shows the benefits of water running for maintaining fitness during injury

Effects of detraining on endurance capacity and metabolic changes during prolonged exhaustive exercise.

Study that shows the effects of detraining(going from 6-10hours a week of training to one 35min intense effort.(endurance capacity decreases a lot while VO2 doesn't, this could mean that only one workout at high intensity per week can maintain your VO2max, but your endurance drops big time).

Anaerobic capacity--theoretical basis and methods for practical testing

Can improve Anaerobic Capacity by 10% in 2months.

Reduced training volume and intensity maintain aerobic capacity but not performance in distance runners.

A Taper of both Intensity and Volume leads to reduced performances while a reduction in volume while keeping the intensity up improves performance.

Carbohydrate-loading and exercise performance. An update.

Study shows that Carbo loading is NOT beneficial before competitions of less than 5minutes or for moderate runs ranging from 60 to 90min. It does improve performance for high intensity efforts of 90 minutes or more.

Effects of recovery beverages on glycogen restoration and endurance exercise performance.

Study that shows that a Carb-protein mixed drink is more effective in recovery than a normal sports drink with just carbs.

Effect of caffeinated coffee on running speed, respiratory factors, blood lactate and perceived exertion during 1500-m treadmill running.

Suggests caffeine can have performance nehancing qualities.