I made a few comments on weight training in yesterday's post.. here is Claus' response. Excellent! Thank you for taking the time to contribute!
Hi Tim, I value your effort to provide advice on training and your ability to combine scientific and empiric knowledge. But I disagree with the following quote: "I firmly believe that lifting weights is a good thing as it improves the oxygen carrying capacity of the muscle and improves economy."
A few years ago I did a review study on strength training for endurance athletes. In most scientific studies it´s generally agreed that adaptations from endurance and strength training are very different and mostly works in opposition to each other. I focused mainly on cycling and running and their very different approaches. Both sports were concerned about hypertrophy and the related weight gain, relative decreased capillarization and increased distance for O2 an CO2. The Danish National Junior Team experimented with very high intensity weight training: 2 sets of 3 reps with 5RM, in leg extension, leg curl, leg press and calf raises. They performed a 45 min. TT on track, 5-7% faster than before - without any unwanted side effects. Runners used almost exclusively plyometrics and drills directed towards the SSC (stretch-shorten-component) of, mainly, the achilles tendon and thereby improving running economy. A famous Swedish study found that weekly running of up to 120 km elicits optimal running economy and after that it´s a matter of diminishing returns. Unfortunately Danish long distance running has adopted the short/fast concept and we haven´t had any sub 2.12 marathoners for years. For distances up to half marathon I believe you can reach a lot of your potential by doing up to 120 km/week, if you carefully and intelligently mix training as you obviously do. You can´t compare different people, but in our running community we´ve had relatively good success by just running pretty slowly - no concerns towards speed - only frequent competition in 5 and 10 km races. With an, embarrassingly slow, average speed of 4.30 min/km one guy ran 2.19 with 100 miles/ week and I ran 2.32 on 50 miles/week on this ridiculously slow pace! The slow pace reduced the risk of getting injured, but we might have had even better results if we had differentiated the stimulus more. If nothing else it would have been more exciting with the variation. Now I´m a firm believer in a more varied and programme, with lots of different paces and workouts, and follow your training and thoughts daily and with great interest. Bottom line: I think most people will get a long way by just getting/being able to do 6-8 consecutive weeks of 80-120 km/week, which is by no means an easy task for most people.
My response: certainly lots of anecdotal and scientific evidence to cover any argument we can start. There certainly are a lot of proponents for weight lifting as there are opponents. I still believe there is value in weight training perhaps for the injury prevention it can give. Particularly in the 'recreational' runner. An elite runner may be another story. I think an elite runner is better off lifting (if at all) in the off season as weight lifting is huge energy drain for key training and volume. Hill repeats are better.
Also, correcting muscle imbalances?
Increasing bone density?
As far as hypertrophy goes, wouldn't that be determined more by diet? If I lifted weights and ran but maintained a slight caloric deficit wouldn't it be impossible to gain muscle mass? I think too that people who just begin a weight training program will experience weight gain immediately- not from increased muscle- but from increased water and glycogen storage.
With the high mileage I would have to point more towards anecdotal evidence in world class runners. Even Rodgers Rops was running 200k per week in preparation for running a 58:00 1/2 marathon. I think the answer lies somewhere in the adaptation process where a younger or newer runner may benefit more from lower mileage- but once they adapt to that mileage then the stimulus needs to change in order to bring about gains. Using intensity would be one way to do that but with intensity the risk is certainly higher. In regards to the marathon specifically- intensity needs to stay appropriate to the metabolic processes required for the marathon. So changing the stimulus to a higher volume seems more effective to the marathon goal rather than increasing intensity?