As we head into peak #marathon training season, there may be occasions when your #endurance #training is reduced or temporarily stopped due to injury or bad weather. Although training adaptations are reversible and may result in reduced performance when training resumes, it’s important that you don’t panic.
A well-planned and structured cross-training programme can help maintain your physiological and psychological fitness until you’re back on your feet again.
Short term (<1-2 weeks) reductions in training (i.e. due to bad weather) are unlikely to cause any issues with your level of fitness. The first stage of de-training is likely to occur within 2-3 weeks and may result in a reduction of VO2max (5-7%). These changes occur at a ‘central’ level (i.e. at the heart rather than in the skeletal muscle) and so alternative exercises can be introduced to prevent de-training and the reduction in VO2max. The second stage takes place over a longer period of time (8-10 weeks) and may result in VO2max returning to pre-training levels. Any rate of decline depends on your training status prior to your injury (Mujika & Padilla, 2000). This second stage of de-training is more specific to skeletal muscle and may mean that your body becomes less efficient at utilising fat stores. This places greater reliance on muscle glycogen during exercise at the same intensity. There may also be significant increases in blood lactate levels at the same work rate and decreases in muscle mass during longer periods of de-training (>8 weeks).
So, what should you do if you have to reduce your training?
Any cross-training programme should be planned in consultation with your GP, consultant or physio. As a rule of thumb, cross-training should be a sport specific as possible whilst avoiding any further aggravation of your injury. For runners, a treadmill is the obvious option provided there is no injury risk. Always ensure the gradient is set at 1% to take the lack of air resistance into account when running indoors (Jones, 1996). Cross-training using an elliptical trainer may be a suitable, sport-specific option. For all cross-training sessions, it’s important to maintain the same frequency, relative intensity (i.e. 80% maximum heart rate), and duration as your normal training sessions. If you are unable to take part in sport-specific exercise due to injury, arm cranking or deep water running in a swimming pool may help maintain VO2max or prevent a significant reduction. In some cases, you may be able to reduce workload (i.e. by 50%) rather than have a complete break and still maintain aerobic performance for up to 3 weeks. This shows that enforced time off should not always be viewed negatively provided low intensity exercise can be maintained.