New rehabilitation program for intermittent claudication: Interval training with active recovery: pilot study. Ann Phys Rehabil Med. 2011 Jul;54(5):275-81. Villemur B, Marquer A, Gailledrat E, Benetreau C, Bucci B, Evra V, Rabeau V, De Angelis MP, Bouchet JY, Carpentier P, Pérennou D.
Peripheral arterial disease (PAD) is one of the complications of atherosclerosis. Intermittent claudication is the second stage of PAD. In controlled studies on patients with Stage II PAD, intensive rehabilitation training has proved effective for improving the walking distance in this population. The objective of this prospective study was to determine the effects of treadmill interval training followed by active recovery (low-intensity exercise).
METHODS AND RESULTS:
Eleven patients with Stage II peripheral arterial disease were included in a rehabilitation program (mean age 68.3±10.3years) for five days a week during two weeks including global exercises, exercises below and above the level of injury. The interval training program consisted of treadmill training for 30minutes twice a day (morning and evening) with a progressively increased intensity: the first week speed was increased and the second week slope was increased. Each session included five six-minute cycles. Each cycle was made of three minutes of active workout followed by three minutes of active recovery.
All patients improved their walking distance, from a mean of 610 m (120-1930) at the beginning of the program to a mean of 1252 m (320-2870) at the end (P=0.003). All patients were very motivated by the rehabilitation training program. No adverse event was reported.
This study showed that an interval training program with active recovery was effective and safe for patients with Stage II peripheral arterial disease, the patients’ motivation was high. This study must now be validated by a clinical trial.
The protocol used in this study was:
- Walk at 70% of max speed for 3 minutes and alternate with walking 40% for 3 minutes 5 times for a total of 30 minutes.
- Max speed was determined by walking 1 kph (0.62 mph) and increasing that speed 0.1 (kph) until reaching maximum tolerable pain.
- If there was no pain during a walk in the first week, speed was increased 0.1 kph, and if there was no pain in the 2nd week incline was raised half a degree.
- Exercise was done 2 times per day 5 days per week.
- It says the “training included global gym exercises, exercises below the level of injury (for proximal lesions: sit to stand and tiptoe, for medial lesions standing on tiptoes and for distal lesions: toe flexing exercises) and above the level of injury (including cycloergometer training) and treadmill retraining.”
There are a few things I think are interesting about this study. It’s the first one I have read that used active recovery (slower walking); the prior papers I talked about used passive recovery (sitting or standing). Results were very good, with walking distance at 3 kph (1.86 mph) more than doubling in just two weeks. The prior papers seemed to indicate gains come more slowly.
What’s difficult to tell is if the active rest was better than passive rest, or if the gains were fast because the people trained very frequently 2 times per day 5 days per week. My guess is that it’s the increased frequency that’s most responsible. Also it’s difficult to know if the increase in walking distance from this study is the same as others where subjects are tested walking different or varying speeds. That I’m not so sure about, so I wish everyone would include a universal test like the 6 minute walk test so we can compare apples to apples. Finally, it’s impossible to know what effect the additional “global gym exercises” had as they were neither separated out nor quantified. Thus, it’s difficult to say how much effect was from the treadmill training program. Another thing I don’t like about this protocol is that it comes across as fairly complex and confusing to implement, increasing speed one week and grade the next. I wouldn’t want to try and teach it to patients for home or gym use and as such would prefer simpler protocols described in my last blog. So in future blogs I’ll compare this one to other studies as best as I can to see which parts of it are worthwhile.
I’ll have to remember that this protocol is good for an average of 105% increase in max walking distance (MWD) at 3 kph (1.86 mph) after 2 weeks. Which works out to:
- MWD/week is 105%/2 = 52.5%
- MWD/workout (30 min 2 per day) 105%/20 = 5.25%
I am curious about the active rest aspect of this study as I have a patient right now who I started using walk/sit intervals with. It takes him about 5 minutes of rest to recover and go again, so I’ll have to let him try reducing the speed by half and see if he feels he recovers better or worse. The more I think about it, I think that would be a good study. I’ll have to see if it’s been done yet.
As always, if you have any further questions or need for clarifications, please don’t hesitate to ask. Being aware that some of my blog ideas are contentious and occasionally a bit out of the field of my expertise, I encourage my readers to come forth with any questions/comments that are of interest or concern. Your comments are valued and welcomed.
Chad Reilly is a licensed physical therapist, located in North Phoenix, practicing science based medicine with treatment protocols unique and effective enough to proudly serve patients from Phoenix, Scottsdale, Mesa, Chandler, Tempe, Peoria, and Glendale.