If cycling is the most difficult feature of the triathlon for you, it is likely that you spend more time cycling than running; the same goes if the opposite is true. However, the best way to improve your overall race time could be through a well-structured cross-training program, as cycling can improve running ability, and running can help with cycling.
Substituting Cycling for Running
Here’s an interesting story. A professional Norwegian cyclist who was unable to train during the winter decided to replace much of his cycling time with high-intensity running over a four-month period. He reduced his riding volume by 60 percent by substituting cycling with two blocks of interval sessions. The first block consisted of 14 sections over nine days and the second 15 sessions over 10 days. All of the intervals involved running at 90 to 95 percent maximum heart rate. By doing this, although his monthly training volume dropped by 18 percent, the amount of training at 90 to 95 maximum heart rate increased by 41 percent.
Before and after cross-training, certain of his training metrics were measured, including cycling economy, VO2 max, and time-trial performance. After the four-month period, his cycling economy had not improved, as was to be expected, but neither had it declined. The other training metrics, however, had improved: his VO2 max increased by 10.3 percent, while his time-trial performance improved by 14.9 percent.
The study demonstrates how cross-training is particularly effective for improving cycling ability when slow training on the bike is replaced by high-intensity runs. This approach could be particularly useful for those who have difficulty training outdoors during the winter, want to decrease the amount of time spent training without jeopardizing fitness, or simply need a break from monotonous cycling routines.
Replacing Running with Cycling
The above can also work the other way around; for example, using cycling to improve your running can be especially useful if you want to include a high-intensity workout in your regime but suffer from limitations that prevent you from performing running intervals, such as a large Achilles tendon. Cycling can help to train your body to develop a quicker turnover and allow you to create more power, and can provide you with the same cardiovascular fitness benefit with less stress on the body.
If you want to replace some of your running workouts with cycling, you may want to consider using the following training metrics, as suggested by Competitor.
Begin by substituting just one or two runs per week with a 60- to 90-minute cycle ride. After a few weeks, you can replace one of your fast running workouts with a higher- intensity cycling session that includes intervals. You should aim to mimic the structure of your running workout by copying the neuromuscular cadence of a quick leg turnover. Rides must be mainly flat or, at the very most, feature a few mild hills to allow you to maintain a cadence of 90 RPM during high-intensity sections.
Although cross-training is a great way to improve power and strength for either activity, as a triathlete it is important to keep training in both running and cycling. Nothing can replace actual training time in the relevant activity nor build the appropriate muscles to the extent needed to improve your race time.