The popularity of the 5,000 meter race has soared in recent years with racers hitting the pavement to challenge themselves, run for good causes and/or pursue experimental data. Scientific AmeriKen has a scattered history in the event having seen races since 2006, yet through all the varied exercise experiments undertaken through the years, has seen little progression in performance. In this experiment Scientific AmeriKen will push the lines between spectacular success and devastating injury through the exploration of the benefits of Fartlekking, a haphazard style of training involving random speed changes.

For most individuals running a 5K race will utilize a blend of aerobic and anaerobic endurance. However, typical training regiments focus more on improving aerobic capacity by jogging at or below the pace being used in the race. Scientific AmeriKen hypothesizes through sprinting, and thereby focusing on anaerobic endurance, 5K records will fall.

The experiment involves the running in 3 organized 5K events spaced exactly two weeks apart. Training involves alternatively a walk/full sprint or jog/full sprint for a full 3 miles, every two days leading up to the second and third race. Sprints were initiated whenever possible and continued until exhaustion. All runs initiated with a minimum of 2 minutes slow jog for warm-up.

Runs leading up to Fartlek training (Search "seldeen" to view results)
All races are organized 5,000 meter events (approximately 3.1 miles)

May 2007
Sept 2007
Oct 2007
Nov 2007
Mar 2008
May 2008
May 2010
Age: 30
Age: 30
Age: 31
Age: 31
Age: 31
Age: 31
Age: 33
Time: 22:21
Time: 25:04
Time: 24:25
Time: 23:01
Time: 31:33
Time: 26:07
Time: 30:28
May 2011
May 2012
Nov 2012
Age: 34
Age: 35
Age: 35
Time: 27:09
Time: 23:08
Time: 25:21

Baseline and runs during fartlek training

May 11, 2013
May 25, 2013
June 9th, 2013
Age: 36
Age: 36
Age: 36
Time: 24:43
Time: 22:24
Time: 20:59

Impressively, fartlek training led to a personal record after just one month, and it is uncertain how much further improvement is possible. However, Scientific AmeriKen must admit the risk of injury seems high in this type of training and several exercise sessions took place through pain for the sake of science. For this reason Scientific AmeriKen urges caution when attempting this strategy, and emphasizes sufficient warm-ups and paying close attention as to not induce/aggravate injuries. As far as why this technique was so successful will require additional research, however, it is believed that increasing the ability to maintain a full paced sprint also enables maintaining a faster 5K pace causing personal records to fall!

Feel free to join the discussion on this experiment at!


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