"... Half of the mice were allowed to run on a wheel for 45 minutes three times a week, beginning at 3 months. These rodent runners were required to maintain a fairly brisk pace, Dr. Tarnopolsky said: “It was about like a person running a 50- or 55-minute 10K.” (A 10K race is 6.2 miles.) The mice continued this regimen for five months. ..."
Do this every day for five months, year in year out? A 10km/hr pace might not seem fast but I'll bet you most people will not keep this up for long. The will power required, level of exertion and increased injury sees to this.
Starting the Monday after Superbowl I started walking to and from work (1.5 miles) and going on a 50-60 minute walk/jog every other day. I also revamped my diet. This is going from almost no fitness to moderate levels. I've lost 16 lbs. since then, and I'm up to 7km in that 60 minute evening walk/jog.
I really don't see a 9 minute mile (basically a 10k in 55 minutes) as incredibly out of reach. I've gone from a 17 minute mile to a 13:30 mile in less than a month, and that was with a week break from the evening exercise. A 9 minute mile is a decent jog for someone that's at a healthy point.
By the way: evening walks are a great time to listen to podcasts or lectures!
IIRC the Roman Army had hit its sweet spot at a 15-mile (~25km) march a day. They'd force march on occasion, but this was rarely before battle. They wanted their soldiers rested before battle.
I'd guess that exercising much beyond 2 miles/hour is going to be detrimental to your body if done daily. Our bodies were built for endurance, which is why our locomotion is derived from gravity. Our ancestors hunted animals that survived by their endurance.
Bear in mind that after Marius, the Roman army required each soldier to carry quite a lot of non-combat material to improve their logistics. Soldiers became known as "Marius's Mules".
Hmmm, not able to reply to your "reply" so I'll post here:
I'm still confused by that 2mph number, the average human walking speed is 5kph (or 3.1 mph), so to walk at a 2mph pace seems suboptimal and potentially more difficult and dangerous than walking at your "normal" pace would be.
"... the average human walking speed is 5kph (or 3.1 mph), so to walk at a 2mph pace seems suboptimal ..."
The forced march (140 cadence) is really is the realm of special forces. Moving over distance is as much about reliability. A function of carry weight X distance travelled. 5km/hr over distance, 30km+/day with 15kg pack, day after day is difficult going. A 100-120 cadence is more reachable. ~ http://www.ibiblio.org/pub/academic/history/marshall/militar...
For your average person a 140 cadence daily over 10km is probably too hard. Just maybe a 3x week might be enough. But is it enough? From the abstract: 'Endurance exercise rescues progeroid aging and induces systemic mitochondrial rejuvenation in mtDNA mutator mice'
"... The systemic mitochondrial rejuvenation through endurance exercise promises to be an effective therapeutic approach to mitigating mitochondrial dysfunction in aging and related comorbidities. ..." ~ http://www.pnas.org/content/early/2011/02/18/1019581108.abst...
You're not taking into account things like carrying a pack and equipment, and difficult varying terrain. I would assume that these would lower the optimal speed.
By no means. The average marching rate for foot-borne, pre-industrial armies has been a pretty consistent 10 miles a day. Only a few exceptionally well organized forces, like the Roman legions, could march more than that on a regular basis.
I think the Romans largely managed it through building level roads to march on. Most pre-industrial armies were marching off-road. I would be saying walking 2 miles/hour on a tarmac road would be someone's maximum before causing damage. Offroad I'd be saying 1.5, maybe even 1 mile/hour depending on the terrain.
Supposedly, the early US settlers (or maybe it was the conquering US army) utilized native American couriers that could run 30 miles a day like it was nothing. I've seen stats as high as 240 miles in 3 days!
I wish I had a link to the source (I'll dig it up when I have more time). I discovered this while researching "fox walking", the toe-first method of human locomotion that some believe is the natural means of human motion, before the advent of stiff-soled shoes. This skill appeared to become mostly lost in the indigenous populations after the Spanish introduced horses to the Americas.
A search on "native american" and "ultrarunning" should render some good links for those who are curious.
As an aside, as anyone who's ever read Stephen King's "The Long Walk" can attest, sustaining a 4mph walk is quite tough. I mean, who hasn't read that story and tried keeping that pace with GPS in hand?
Not really, if you're forcing yourself to go faster you're likely doing damage. You might be able to go faster for shorter periods or slower for a lot longer. However, I would think if the Roman Legion had been doing 25km in 3 hours I doubt they would have won any wars.
Their forced marches were to make them march longer, not faster. I'm saying 2 miles/hour because the Romans only managed around 1.5 with weight.
My office is three miles from my house. If I walk at a slow, I-don't-want-to-go-to-this-meeting pace, I get to work in forty minutes. Same time for getting home. I did this for five years and I wasn't even in shape.
I'm not arguing that the Romans were slackers. Given the effort it takes to setup a Roman castra, the marching might be the least strenuous part of the soldier's day. Also, my daily walk is on paved sidewalk across mostly level ground, while the Romans often didn't have such advantages.
For an able bodied person walking through a shopping mall, three miles an hour is perfectly healthy and reasonable.
The Roman military manual is precise in how far, how much kit they carry and the pace of a centurian. We know this from scholars such as Judson (1888) who researched the roman military historian, Vegetius (Flavius Vegetius Renatus) [0] Vegetius wrote in detail how the Roman military organised itself: [1]
Kit weight: 30-40lbs (15+kg)
Pace: 40,000 quick step of 2.5ft at a cadence of 100 to 120 steps/min.
(a baseline number still used today in modern Infantry).
Distance: 15-20miles in seven hours
Average Speed: 1-3mi/hr depending on terrain, max by road.
Remember this is a minimum distance, moving a lot of people. What happens bumping up the distances up to say 20-30km per day? I've tried this. I bumped up the distances up to 33km/day over multiple days with 10kg weights. It's brutal. I did this to train for a 240km march in 9 days last year. You can see the type of kit we carried http://www.flickr.com/photos/bootload/4665564383/in/set-7215... and terrain traversed ~ http://www.flickr.com/photos/bootload/sets/72157623796441755... before we hit the mountains. Of the 20 that started only 3 finished without injury, including myself.
This is way beyond the ability of most ordinary people. Even 10km with no carry weight. I can say this because I average 2000km/year on foot with average weight of 1-12kg, 10km at a time. I aimed to run 40% last year but barely did 10% due to injury. I have a lot of data points. I don't see the average person doing even the suggested rate of 10km, 3 days per week at a 10km/hr. In fact the only regular people I see are other runners. This is of course anecdotal. But the figures for the weight of Australians isn't. [3]
A more interesting experimental question would be, "what is the minimum speed/distance you need to do per day to get the maximum health benifit?". At the moment it's 10K steps per day. Hence the reason I'm so active. One alternative to running I suggest is climbing steep terrain ~ http://www.flickr.com/photos/bootload/sets/72157623445003205... You can exert yourself just as much in a much shorter distance and time.
Yes, but only because of gearings. There'll be a similar exertion limit. One of my old bosses was at one point a pro-cyclist, until he ruined his hips and knees. His doctor actually forbid him from cycling so that he would actually stay active into his later years.
All exercise will have a limit on how beneficial it will be to you. Ideally you would want to spread it out across as many joints and muscles as possible so you don't excessively wear on any of them.
I'd think the amount of calories you burn a day is likely to have a greater effect on your health than simply how much you walk/cycle or weight lift.
Burn the maximum calories you can but spread the exercise over as many muscle groups as you can and that will keep you feeling young.
"... the risk of increased injury is easily addressed by choice of exercise - swimming, rowing, etc. ..."
what about your bones?
"... The best exercise for your bones is the weight-bearing kind, which forces you to work against gravity. Some examples of weight-bearing exercises include weight training, walking, hiking, jogging, climbing stairs, tennis, and dancing. Examples of exercises that are not weight-bearing include swimming and bicycling. Although these activities help build and maintain strong muscles and have excellent cardiovascular benefits, they are not the best way to exercise your bones. ..." ~ http://www.niams.nih.gov/Health_Info/Bone/Bone_Health/Exerci...
"... combine swimming/rowing/bicycling for its anti-aging benefits with weight lifting ..."
The study was looking at how endurance exercise reduced mitochondrial damage. Rowing, riding and swimming are endurance sports, so most likely yes.
"... The systemic mitochondrial rejuvenation through endurance exercise promises to be an effective therapeutic approach to mitigating mitochondrial dysfunction in aging and related comorbidities. ..." ~ http://www.pnas.org/content/early/2011/02/18/1019581108.abst...
Do this every day for five months, year in year out? A 10km/hr pace might not seem fast but I'll bet you most people will not keep this up for long. The will power required, level of exertion and increased injury sees to this.