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When Lance Armstrong won the Tour de France back in 1999, he showed us a pedalling style with a very high pedalling rate, even in the mountains. Many experts have referred to this technique as one of the main reasons that Armstrong could beat his opponents so easily. With a high frequency it is easier to remove lactate from the legs, but it requires a high degree of special training to be able to maintain a high pedalling frequency.

What is the best cycling cadence?

For me, cycling pedalling rate has always been some kind of a controversial topic. I am not sure that is possible to change riding style significantly.

Nevertheless, I have tried to adapt some of my riders pedalling frequency to a faster one, believing that this would help them to save energy for the final parts of the races.

My conclusion until now is that it is not possible to make big changes, probably in the area of on average 0-5 rpm higher pedalling frequency. So special training at high frequencies can probably not explain why some riders are able to do it and others are not.

It is also worth to remember that a couple of riders who prefer slow frequencies also perform at world class level (e.g. Serguei Gonchar). Thus, a high pedalling rate per se is not predicting performance even among the best riders in the world. Take a closer look at the riders in the Tour de France and watch the differences.

Slow pedal rate might be a better choice

Ernst Albin Hansen, PostDoc, who is a scientist and previous elite cyclist, has been studying choice of cycling pedalling rate for more than 10 years now. In a study from 2006 he included 9 trained cyclists who rode two rides of 2½ hours at 180W followed by a 5-min all-out trial. Results: There were no significant differences, but trends showing that choosing a slower pedalling rate might be attractive.

Test setup:

• 180W, freely chosen pedalling rate (avg. 95rpm) followed by 5min all-out.

• 180W, calculated pedalling rate (which averaged 73rpm) followed by 5min all-out.

The calculated pedal rate was supposed to result in a minimum oxygen uptake.

Results

When comparing the two setups, some interesting results were found:

• Peak VO2 was lower after riding with freely chosen pedal rate

• Perceived exertion were higher with freely chosen pedal rate (7-9%)

These results indicate that riding like Armstrong might not be the answer for optimal cycling pedalling rate. If some of you think this study is interesting, you could consider trying the tests me ntioned above in the gym during the winter. It is guaranteed a good workout for you.

Mountain Biking Injuries in Children and Adolescents

Abstract:

Over the last decade, the sport of mountain biking has experienced extensive growth in youth participation. Due to the unpredictable nature of outdoor sport, a lack of rider awareness and increased participation, the number of injuries has unnecessarily increased. Many believe that the actual incidence of trauma in this sport is underestimated and is just the 'tip of the iceberg'. The most common mechanism of injury is usually attributed to downhill riding and forward falling. Although rare, this type of fall can result in serious cranial and thoraco-abdominal trauma. Head and neck trauma continue to be documented, often resulting in concussions and the possibility of permanent neurological sequelae. Upper limb injuries range from minor dermal abrasions, contusions and muscular strains to complex particular fracture dislocations. These are caused by attempting to arrest the face with an outstretched hand, leading to additional direct injury. Common overuse injuries include repeated compression from the handlebars and vibration leading to neurovascular complications in the hands. Along with reports of blunt abdominal trauma and lumbar muscle strains, lower extremity injuries may include various hip/pelvic/groin contusions, patellofemoral inflammation, and various muscle strains. The primary causes of mountain biking injuries in children and adolescents include overuse, excessive fatigue, age, level of experience, and inappropriate or improperly adjusted equipment. Additional factors contributing to trauma among this age group involve musculoskeletal immaturity, collisions and falls, excessive speed, environmental conditions, conditioning and fitness status of the rider, nonconservative behavioural patterns, and inadequate medical care. The limited available data restrict the identification and understanding of specific paediatric mountain biking injuries and injury mechanisms. Education about unnecessary risk of injury, use of protective equipment, suitable bikes and proper riding technique, coupled with attentive and proper behaviour, are encouraged to reduce unnecessary injury. This article provides information on the causation and risk factors associated with injury among young mountain bikers, and recommendations to minimize trauma and enhance optimal performance and long-term enjoyment in this outdoor sport.

Mountain Biking–Related Injuries Treated in Emergency Departments in the United States, 1994-2007

Abstract

Background: Injury research on mountain biking has been mostly limited to examining professional riders and off-road biking. Mountain bikes represent the largest segment of bike sales in the United States. Recreational mountain bike use is popular and understudied.

Methods: A retrospective analysis was conducted with data from the National Electronic Injury Surveillance System of the US Consumer Product Safety Commission for patients aged ≥8 years from 1994 through 2007. Sample weights provided by the system were used to calculate national estimates of mountain bike–related injuries based on 4624 cases. Bivariate comparisons between categorical variables were assessed with injury proportion ratios and 95% confidence intervals.

Results: Nationwide, an estimated 217 433 patients were treated for mountain bike–related injuries in US emergency departments from 1994 to 2007, an average of 15 531 injuries per year. The annual number of injuries decreased 56%, from a high of 23 177 in 1995 to 10 267 in 2007 (P < .001). The most common injuries were upper extremity fractures (10.6%) and shoulder fractures (8.3%). Patients aged 14 to 19 years sustained a greater proportion of traumatic brain injuries (8.4%) than did patients aged 8 to 13 years and ≥20 years combined (4.3%). A greater proportion of female riders (6.1%) than male riders (4.5%) were hospitalized.

Conclusion: Mountain bike–related injuries decreased from 1994 to 2007. Upper extremity fractures were the most common injury. Girls and women may be more likely than boys and men to sustain more severe injuries requiring hospitalization. Despite the decline over the past decade, more can be done to improve safety and reduce injuries in this popular recreational activity.

Warning for athletes:
Risk of inadvertent doping with clenbuterol when travelling to China

The Manfred Donike Institute for Doping Analysis (MDI) and the Center for Preventive Doping Research of the German Sport University Cologne are warning athletes from risks of inadvertent doping with the ß2-agonist clenbuterol when travelling to China.
An investigation, presented on the 14th of February 2011 at the Cologne Workshop on Doping Analysis, showed that the analyses of the urine samples of 28 travellers, returning from China to Germany, resulted in findings of low concentrations of the doping substance clenbuterol in 22 out of the 28 urine samples. The results were obtained between the 15th of September 2010 and the 15th of January 2011. The findings are most probably due to a food contamination problem, potentially caused by misuse of clenbuterol as growth promoter in stock-breeding.

Dispensatie geneesmiddelen - Veranderingen per 1-1-2011

Ook per 1 januari 2011 is er weer wat veranderd met betrekking tot dispensaties en meldingen. Deze laatste procedure bestaat niet meer. Het is dus niet langer nodig een meldingsformulier in te vullen.

In de praktijk betekent dat geen melding meer voor veelgebruikte medicijnen als Airomir (salbutamol), Salbutamol (salbutamol), Serevent (salmeterol), Ventolin (salbutamol) en Seretide (salmeterol/fluticason). Ook voor corticosteroïden per inhalatie, zoals Qvar (beclometason), Pulmicort (budesonide), Alvesco (ciclesonide) en Flixotide (fluticason) en evenmin voor locale injecties met bijvoorbeeld Celestone (betamethason), Depo-Medrol (methylprednisolon) en Kenacort (triamcinolon).
Voor alle overige medicatie is een dispensatie noodzakelijk.

Dispensatie

Wanneer je om medische redenen medicijnen gebruikt die op de dopinglijst staan, kan je daar dispensatie voor aanvragen. In de praktijk komt het het vaakst voor dat het gaat over:
- anti-astmamiddelen als fenoterol, formoterol en terbutaline;
- methylfenidaat (bv Concerta), voor ADHD;
- insuline (in het geval van diabetes); of
- bloedrukmedicijnen (zoals diuretica en -in sommige takken van sport- beta-blokkers).
In principe kan voor elk geneesmiddel dispensatie worden aangevraagd.

Lees verder: https://gds.dopingautoriteit.nl/#veranderingen