I noted that when I run regularly – as I usually do when not on vacation – I tend to eat less and more healthy stuff… Indeed, there is scientific data indicating that physical activity reduces appetite! People who can eat right after exercising tend to gain more weight than those fasting for some time after exercising.
Of course, there’s an association between weight and performance. As a rule of thumb, there is a 1% change in tempo per kilogram body weight. For example: a weight decrease of 4 kg will make a time difference of approximately 10 minutes over marathon distance for a slow runner (4 hours).
Also during a race, weight changes affect performance. Elite runners consume minimal fuids during racing. Some African runners consume a hypocaloric diet in the weeks before an important race.
Worlds class runners are generally slim… Body mass index (BMI) is generally considered normal between 18.5-25. I have calculated BMI for some top marathon runners, as well as historical heros. These world class runners tend to have a BMI under 20. In addition, I added some interesting athletes…
| Marathon Time | Athlete | Nation | Age | Height | Weight | BMI |
| 2:04:26 | Haile Gebrselassie | ETH | 35 | 165 | 55 | 20.2 |
| 2:04:55 | Paul Tergat | KEN | 39 | 182 | 62 | 18.7 |
| 2:05:24 | Samuel Wanjiru | KEN | 21 | 163 | 52 | 19.6 |
| 2:05:30 | Abderrahim Goumri | MAR | 32 | 168 | 59 | 20.9 |
| 2:06:05 | Ronaldo da Costa | BRA | 38 | 167 | 52 | 18.6 |
| 2:06:17 | Ryan Hall | USA | 25 | 178 | 59 | 18.6 |
| 2:07:23 | Viktor Röthlin | SUI | 33 | 174 | 57 | 18.8 |
| 2:07:22 | Stefano Baldini | ITA | 37 | 176 | 62 | 20.0 |
| 2:08:54 | Eric Wainana | KEN | 34 | 174 | 55 | 18.2 |
| 2:46:43 | Lance Armstrong | USA | 178 | 78 | 24.6 |
Last week: 45 km. I did not complete the planned long run. Due to pain in my right hip I have to pause my training for some days. It’s only 8 weeks to my planned half marathon. However, the pain’s there for 3-4 weeks (since the beginning of August) and I fear if I go on there will be a problem… Don’t know if it’s the iliotibial tract.
Filed under: Personal Log, Photography, Training | Tags: intervall, iPhone, Photography, sweat rate, tempo run, Training
It’s getting cooler, autumn is coming. Makes it easier to run faster… 
Today, the sun gave long shadows – as shown in the photo I took with my iPhone. For more runner photos see my website.
On Monday, I did a tempo test run over 5k, finishing in 22:54 (4:35 pace @ 93% of max heart rate). Intervals on Wednesday (5×1.2k), and 10 miles yesterday on Saturday with 5:50 pace. I feel quite tired although it was a low mileage week.
I calculated my sweat rate again, it was 125 mL/km at 16°C. Not much less than the 145 mL/km at 26°C two weeks ago.
10 weeks to Lausanne HM!
My first >70 km week (43 miles)! Two interval trainings, a long run, and two slower runs.
Of the total training time of 7:50:32, my heart rate was 57% of the time in the 75-85% zone, 16% in the 85-90% zone, and 15% in the 90-100% zone.
I feel a slight soreness on the lateral sides of both hips at the ilio-tibial tracts. But the knees are okay.
It’s 12 weeks to the half marathon in Lausanne…
Another long run. For the 24 kilometers, I managed a negative split, running progressively faster. The half marathon distance took me 2:12:48 at 80% of my maximal heart rate.
During todays long run, I lost 2.7 kg weight (net loss, 3.2%). I drunk 810 mL water during the 2.5 hours (320 mL/hour). So my gross loss would have been 3.5 kg, that’s 4.1% of my body weight. Afterwards (and over the last 3-5 km), I was a bit thirsty, so I could and should have taken in some more water.
Under these weather conditions – sunny day, temperature 26°C, no wind, and humidity around 60% – I loose around 1400 mL fluid per hour, or 146 mL per kilometer.
Researchers at the Salk Institute in San Diego reported that they had found two drugs that did wonders for the athletic endurance of couch potato mice. Read more in the NY Times…
Filed under: Training | Tags: dehydration, fluid replacement, hyponatraemia, long distance running, marathon
The demands of marathon running can result in substantial sweat losses (>2% body mass, i.e. more than 1.6 kg for a 80 kg individual) and dehydration.
Excessive fluid intake during long distance running such as a marathon can result in dangerous situations. Slower runners (>4 hours for a marathon) tend to over-replace fluid losses which can result in hyponatremia and serious health hazard. Elite athletes typically ingest about 200-800 mL water per hour. Hyponatremia typically manifests as vomiting; collapse is less specific as other conditions also induce exercise-associated collapse such as postural hypotension (especially after finishing).
During endurance exercise, about 75% of the energy produced from metabolism is in the form of heat, and only the remaining 25% of energy available can be used for movement! Heavier runners tend to retain more heat than lighter individuals. However, replacement of lost fluid may negatively affect performance, as decreasing body mass during a race reduces oxygen cost (better running economy).
Using thirst to gauge safe fluid replacement appears more reasonable than earlier recommendations. Until the early ’70s, the guidelines for fluid ingestion during exercise were not to drink. By 1996, guidelines stated, “individuals should be encouraged to consume the maximal amount of fluids during exercise that can be tolerated without gastrointestinal discomfort up to a rate equal to that lost from sweating“. The latter thus appears not advisable anymore. To prevent exercise-associated hyponatremia it is advisable to actually loose some body weight during a marathon (>0.75 kg). This means that weight loss should not be fully compensated by water intake. Drinking to maintain bodyweight may impair exercise performance by inducing a weight penalty and may increase the probability of exercise-associated hyponatraemia in slow marathon runners.
My long run was very pleasant today, listening some great music, and the weather was fine. I did 22k, and passed the half marathon distance (21′098 m) after 2:13:25 hours. Heart rate averaged 79% of my maximum. What a good feeling to finish the week!
Filed under: Personal Log, Training | Tags: Haile Gebrselassie, marathon, training plan, Viktor Röthlin, world record
After starting to run regularly in 2007, there have been quite some low-intensity weeks the winter. Too much work… After realising its effects on my mood, I reduced my workload and increasedrunning training. So this was my first >60 km week, yeah!
I started to use a training plan by Viktor Röthlin, our Swiss marathon professional. He’s the fastest marathon runner in the german-speaking countries in Europe. His personal best is 2:07:23 at the Tokyo marathon in 2008. Not quite the world record hold by Haile Gebrselassie from Ethiopia (2:04:26 in Berlin, 2007) but still…
I like the training plan – it’s internet-based accessible at VicSystem – because of the flexibility and variety. The plans allows to specify training days of the week and change them also in the short-term. The long runs are to be run in considerably faster pace than traditionally recommended.
The system also allows to plan for races which then are specifically incorporated in the plan. So I am thinking about my first race… Maybe a half marathon? There is one in Lausanne on October 26, 2008…? Let’s see.
Filed under: People, Training | Tags: cycling, lactate threshold, Lance Armstrong, marathon, oxygen uptake, physiology, VO2max
In November 2007, Lance Armstrong finished his second marathon in New York in 2:46:43 hours. He improved his time by 13 minutes. In 2006, he had run the NY Marathon in 2:59:36 hours – where he suffered a stress fracture. This year, he finished his third marathon in Boston in 2:50:58 hours.
It’s interesting to see what an athlete with an extremely high oxygen uptake capacity achieves in running. Maximal oxygen uptake is – among other factors – a determinant of performance which in the case of Lance as a cyclist was extraordinary! Think of his Tour de France triumphs… However, running strains the joints, ligaments and bones differently than cycling. All the weight lasts on the legs and feet. Therefore also intersting: his weight is 78 kg and his height 178 cm. So Lance is not quite meager, his BMI is well above the top-runner’s range: 24.6!
He was serially tested over 8 years from the age of 21 years by the physiologist Edward F. Coyle at The University of Texas at Austin. Lance’s maximal heart rate at the age of 28 years was still around 200/min. Maximal oxygen uptake (VO2 max) was as high as 72 to 80 ml/min/kg, and his lactate threshold was 78% of maximal oxygen uptake! The original scientific publication appeared in the J Appl Physiol 2005.
I think there are some interesting points to learn from him:
- VO2max is not the best indicator of running performance as it does not include running efficiency
- adequate preparation is mandatory, especially for joints and bones
