Downhill running sounds easy. Gravity will take you down a hillside, or slope on the road that much quicker. The problem is it could also be a quick way to muscle soreness and hampered training. Dr Jason Karp shows you how to combat this and become a great downhiller.
Physiology of Downhill Running
If you’ve ever run a race with long or steep downhills, you know what running downhill can do to your legs. Even though running uphill seems harder, it’s the downhills that cause the biggest problems. The reason downhills are so tough is because of the gravity-induced eccentric muscle contractions, during which your muscle fibres are forced to lengthen as they put the brakes onto slow your descent, causing microscopic tears and soreness.RELATED: RECOMMENDED PLANS FOR YOU
During a race, or when training, this muscle damage decreases your muscles’ ability to produce force and this slows your pace on the flat and uphill portions of the race/training run. Afterwards you may suffer from delayed-onset of muscle soreness (DOMS). DOMS is an inflammatory response, accompanied by that tender-to the-touch feeling in your muscles that lasts for a few days as your muscle fibres heal.
Eccentric contractions are also unique in that fewer muscle fibres are active compared to other types of muscle contractions.This means that the force generated is distributed over a smaller area of muscle – this creates greater tension and even more damage.
Downhill running also affects running economy, the amount of oxygen you consume to maintain a given pace.A number of studies have shown a significant decrease in running economy for up to one week following a 30-minute downhill run on a 10 to 15 percent grade.
Damaging muscle fibres with eccentric contractions makes them heal back stronger, protecting them from future damage. A study published in the Journal of Applied Physiology in 1985 found that just a single 30-minute downhill run at a 10 percent grade had a prophylactic effect on muscle damage and soreness for up to six weeks.
This means that although you can expect your muscles to be sore after your first downhills, subsequent efforts will create less soreness. Add downhills to your training a little at a time. Start with a short, gradual slope (2-3 percent), and progress to steeper and longer descents.
You should treat downhill workouts as hard sessions – consequentially you should make sure that you are fully recovered before your next hard workout, irrespective as to whether this is on the flat, uphill or downhill. Time has the greatest effect on healing your muscle fibres from the eccentric contractions of downhill running. So make sure you back off of the hills in the final few weeks before a race.
Downhill run technique
One thing to be aware of when training downhill is your running technique – it’s all too easy to over-stride. Instead of focusing on reaching forward for a longer stride – which already happens from the pull of gravity – you should emphasise quicker leg turnover, which will keep your momentum going forward.
Running on trails requires even greater caution, since you won’t have as much time to decide where to place your feet with the faster speeds attained on the downhill portions, so look ahead a few steps so you can prepare, since the footing on trails is often unreliable.
“If you train smart enough, you’ll be able to charge up the other side of the hills while your competitors are labouring from the downhill damage”
Tired quadriceps and faster than usual speeds during downhill races require a keen sense of pace, confidence to stick to your plan and don’t chase those who have taken the pace out too fast. Use a good dose of self-restraint.
Because momentum will make your goal pace feel much easier than it does on the flat, it’s important to understand how to hold your speed on the downhills, to achieve your designated end race time and not tire your legs so that you have less energy during for the later stages.
This is what Nicole Prause, Ph.D., had to say about winning the 2007 Pocatello Marathon in Idaho, which drops 457 metres in the first 22.5 kilometres.“I had a goal pace in mind and a GPS for feedback every 400 metres. I found it extremely difficult to make adjustments to maintain an even pace,” she says. “One quarter was too fast and, although I tried to slow down, the next quarter would have a steeper drop.
What felt hard was far under my planned split, and what felt easy was still under split. Having run several downhill races since, I think the downhill needs to be considered specifically in setting a goal pace.” The best downhill running skill to develop during training is the ability to run with different exertion levels (rather then percentage of heart rate, if using a heart rate monitor).
For example, ‘learn’ to simulate 10km race pace intensity, rather than 10km pace, while running downhill. While your pace will be faster than 10km pace, you’ll develop the awareness and control to differentiate between different paces for different downhill environments.
If you know your next race will involve lots of downhills, then you need to train for it – see my suggested, specific workouts. If you train smart enough, you’ll be able to charge up the other side of the hills while your competitors are labouring from the downhill damage.
Try This: Downhill Workouts
To train for downhill races, try these workouts.
For complete downhill races:
*4 x 800 metres downhill (2-3% grade) at 5k race pace effort
*3 x 1.5 to 2km downhill (2-3% grade) at 10km race pace effort
*5 x 100 to 200 metres downhill (6-8% grade) at 5km race pace effort with walk back up hill recovery
For races with both downhills and uphills:
*4 sets of 1.5 to 2k downhill (2-3% grade) at tempo* pace effort + 400 metres uphill at 5k race pace effort
*4 sets of 800 metres uphill + 800 metres downhill (2-3% grade) at 5k race pace effort with 3 minutes’ recovery
*Tempo runs are run at a pace that produces ‘sustainable discomfort’. They equate to approximately 75-85% of heart rate max (if using a heart rate monitor) or an intensity at which you’d be able to converse, but only in short clipped sentences.