Cycling training: recent research on bone density in pro cyclists makes for uncomfortable reading

Cycling has traditionally been regarded as one of the healthiest sports around
This article:
Discusses the link between exercise, bone mineral density (BMD) and health;
Looks at new research on BMD in road cyclists and explains why they may be at greater risk of bone health problems;
Makes practical recommendations.
Cycling has traditionally been regarded as one of the healthiest sports around, and its impact-free nature has made it particularly appealing to those concerned about their joint and skeletal health. However, recent research on bone density in pro cyclists makes for uncomfortable reading. Andrew Hamilton explains.
The height of the cycling season is upon us and with it the big tours such as the Tour de France and the Giro d’Italia. During these events, the professional cyclists typically churn out hundreds of kilometres per week under race conditions. Meanwhile, even lesser mortal such as club and sportive riders will be upping their mileages, spurred on by forthcoming races and events.
Assuming that cyclists undertake a properly structured training programme with manageable increases in training volumes and intensity, and that they allow adequate time for recovery with good nutrition, the physiological and health effects of increased cycling performance will almost always be beneficial. For example, research shows that increasing the intensity of aerobic type exercise such as cycling confers several health benefits such as:
Enhanced insulin sensitivity(1);
Reduced blood pressure(2,3);
Improved blood cholesterol profile(2,3);
Reduced body fat(4);
Reduced risk of coronary heart disease (as the result of the above)(5,6);
Better quality of life in older age(7);
However, one area where (unlike many other forms of exercise) cycling might not deliver health benefits is bone health, or more specifically, increasing bone mineral density (BMD – see below).
Importance of bone density
Why are high levels of BMD important? In very simple terms, this is because low levels of BMD are associated with an increased risk of osteoporosis. Osteoporosis is a disease that affects mainly (but not exclusively) older people, in which bones gradually become more fragile and likely to break. These broken bones are also known as fractures and typically occur typically in the hip, spine and wrist.
Osteoporosis (which quite literally means ‘porous bones’) is often known as the ‘silent crippler’ because it often progresses painlessly and unnoticed, until a bone actually breaks. Although any bone can be affected, fractures of the hip and spine are particularly problematical because they can produce a number of long-term complications including loss of ability to walk and permanent disability, loss of height and severe back pain. Although the precise mechanisms are poorly understood, the hallmark of osteoporosis is a reduction in skeletal mass caused by an imbalance between bone breakdown (resorption) and bone formation. This results in reduced bone mineral density.
Although osteoporosis is poorly understood as a disease process, we do know that being physically inactive is a major risk factor for developing osteoporosis. This is because vigorous ‘bone-loading’ physical activity is very effective at stimulating the uptake of calcium into bones, thereby helping to build bone mass in earlier years, and reducing the loss of bone mass in later years(8).
Bone loading exercise
Research has shown that the higher the muscular and impact load (gravitational) forces, the higher the BMD produced; so for example, gymnasts whose sport requires high loadings and impacts tend to have higher BMDs than endurance runners(9). By contrast, those who participate in sports with plenty of muscular motion, but without substantial loading (eg swimming) do not achieve the high BMDs of sports with higher loading(10). There’s also evidence that activities which develop strength (such as weight training) are particularly effective at producing high BMDs in the hip and spine(11,12).
So how does cycling fit into the equation? Well, muscular loading during cycling can be very high, especially during sprinting – for example on the track. On the other hand, the smooth spinning nature of the pedalling action and the fact that cyclists are supported by their saddle means there’s virtually no bone loading associated with gravitational impact (unlike the shock of foot-strike during running or field sports). In distance road cycling, therefore, where sprinting is only a minimal component, the degree of total bone loading is likely to be quite low, which has prompted researchers to look at the issue of BMD in cyclists more generally.
Overall, the balance of research suggests that road cyclists do not benefit from increased BMD in the same way that other sportsmen and women do (see below). But, more worryingly, some studies indicate that road cycling could actually have a detrimental effect on BMD. For example, French scientists found recently that compared to healthy non-cycling males, road cyclists had lower levels of BMD, and this was despite the fact that they were consuming significantly more dietary calcium (considered essential for bone health) than their sedentary counterparts(13). The researchers speculated that the combination of high training volumes of these cyclists combined with lack of bone loading might be a factor and now a brand new study on pro cyclists appears to bear this out (14).
Box 2: Road and mountain biking
Unlike road cycling, bone loading from shock absorbing impact is a factor in mountain biking. So do mountain bikers have higher BMD levels than roadies? A US study compared the BMDs of 16 mountain bikers, 14 road bikers and 15 active non-cyclists (controls), where they looked at the femur, lumbar spine, and total body bone mass using a technique called DXA(15). The cyclists were training for an average 11 hours per week and had been cycling for around eight years.
The results showed that (when adjusted for body weight and controlled for age), BMD was significantly higher at all sites in the mountain cyclists compared with the road cyclists and controls. The researchers concluded that ‘endurance road cycling does not appear to be any more beneficial to bone health than recreational activity in apparently healthy men of normal bone mass’.
Meanwhile, another DXA study by Brazilian scientists found that while well trained young cyclists were aerobically fitter and had more muscle mass, their bone BMDs were no higher than sedentary controls of the same age(16). Other studies have also found that the BMD of road cyclists is no higher than in sedentary adults of the same age (17-19), which is obviously less than desirable from a bone health perspective.
Pro cyclists
In the study, scientists in Sweden, France and the UK compared the BMD at several skeletal sites of 30 male professional cyclists with 30 similarly aged males (controls), using DXA. The cyclists were all racing in professional teams at the time of the study, and had participated in at least one of the main 3-week stage races (Giro d’Italia, Tour de France or Vuelta a España) in each of the previous three years. The controls were all healthy but had cycled less than one hour per week and had not performed weight-bearing exercises (ie running or resistance training) for more than one hour per week for three years prior to the time of the study.
The results showed that overall, the pro cyclists had significantly lower levels (9.1% less) of BMD than the control group; more worrying was that in the lumbar vertebra of the lower back and femoral neck (ball joint at the top of femur), BMDs were 16% and 18% lower respectively. The researchers commented that although their study examined pro cyclists training and racing for upwards of 22-25 hours a week, the findings could have implications for road cyclists more generally. Of particular concern is that cyclists are at risk of traumatic injuries from falls or collisions, something that can easily lead to fracture.
Conclusion and recommendations
So where does this leave cyclists who are concerned about longer-term bone health? Well, it’s important to emphasise that reduced BMDs in road cyclists seems to be associated with large volumes of training (over 20 hours per week). The majority of recreational and club riders will not fall into this category. However, even recreational cyclists are unlikely to be benefiting from the increased BMD associated with many other forms of exercise and which can help prevent osteoporosis later in life.
The good news according to Frederic Campion, one of the researchers involved in the study above(19), is that resistance training and running are both excellent bone mass builders; adding small amounts of these activities into your weekly programme is not just an excellent bone health insurance policy, recent research suggests that they could even help improve your cycling – but that’s another story!
References
1. Diabetes Care. 1996;19:341-9
2. Med Sci Sports Exerc. 2004;36:533-53
3. Med Sci Sports Exerc. 2001;33:S438-45
4. J Clin Densitom. 2010 Jan-Mar;13(1):43-50
5. GAm J Cardiol. 2000;86:53-8
6. N Engl J Med. 2002;346:793-801
7. Med Sci Sports Exerc. 2001 33: S551-S586
8. J Bone Miner Res. 1995 10:586-593
9. J Sports Med Phys Fitness 2009 ; 49 : 44 – 53
10. Int J Sports Med. 2010 Apr 29. [Epub ahead of print]
11. Sports Sci 2004 ; 22 : 645 – 650
12. Med Sci Sports Exerc 1997 ; 29 : S5
Researched by KATIA C. ROWLANDS – PILATES INSTRUCTOR & PERSONAL TRAINER – 0825134256

U3A

Monday  8th September 2014
–  Shoreline  Series 2  :  Episode  9 of 13
The  Pondoland Coast
From East London to Port Edward : Transkei Travel and visit shipwrecks
The Wild Coast rivers, the East Coast mussels, the Pondo culture & history
10H00  at Formosa Garden Village Lounge
Co-ordinator:  Christo Vlok  044-533-5155

Tuesday  9th September 2014
–  Italian Conversation
09H45  at 12 Challenge Drive
Co-ordinator:  Brenda Hardy  044-533-5489

Wednesday  10th  September  2014
– The Wings above Africa
Stewart Lithgrow tells and shows us
what it’s like to be part of an aerobatics team
10H00  at Formosa Garden Village Lounge
Co-ordinator:  Lynette Timme   044-535-9041

Wednesday  10th  September  2014
–  U3A Plett  Social Bridge Club
General lessons for improving players, help
and supervised Bridge in a friendly atmosphere
13H30  at the Angling Club
Co-ordinator:  Michael Webb  082-226-7280

Friday  10th  September  2014
–  French Conversation
10H00  Meet at 7 Glennifer Street
Co-ordinator:  Merle Decot  044-533-5879

Friday  10th  September  2014
–  Mah-jong
Learn and play this ancient and fascinating game
13H30  at Formosa Garden Village Small Dining Room
Co-ordinator:  Amelia White  044-533-0113

Myofascial Release Using the Foam Roller

What is myofascial release? The word ‘myo’ means muscle and ‘fascia’ means band.  Fascia is a strong but very flexible connective tissue which envelopes every structure (organs, muscles, tendons, bones) of the body, providing support and protection. The myofascia can get tears in them and if they don’t heal properly, the various layers of fascia can cause adhesions.  These adhesions stop the muscles working as freely and easily as they should which can then cause pain and discomfort. Myofascial release is a manual therapy used in the treatment and rehabilitation of muscle and fascial tension. What are the benefits of it? The main benefit of Myofascial release is that it will help to release the adhesions but there are other benefits too, including: Helps to disperse knots and tightness in your muscles Helps prevent injuries Helps with increasing the range of motion of joints Helps to relieve muscle soreness Using the foam roller The foam roller can be used for self-myofascial release.  By performing self-myofascial release techniques on a foam roller, you will be able to help release tight fascia and encourage the muscles to become fully functional again. The release techniques on the foam roller involve rolling each muscle group over the foam roller until a tight or tender area is found.  When the tight spot has been identified, pressure of your own body mass should be held on the area for 30-60 seconds until the muscle begins to release. The following areas often have tight spots: Piriformis – The piriformis muscle is a pear-shaped muscle located in the gluteal region.  Begin by sitting on the foam roller, have one hand resting on the floor behind you for support.  Cross one foot over the opposite knee and start to roll on the posterior hip area.  The stretch can be increased by using your free hand to pull the knee toward the opposite shoulder. Hamstrings – Place the hamstrings on the roller and use the hands behind you to keep the hips off the floor.  Roll from the knee to the hip.  Try turning the legs out from the hip and in from the hip to massage all the areas. Rhomboids – The rhomboids are a skeletal muscle which helps to support the scapula.  Place your upper back on the roller and cross the arms to the opposite shoulder.  Engage the core muscles and lift the hips, keep the head in a neutral position.  Roll the mid back area over the roller.  You can also move gently to each side. The Lumbar Region It is not recommended to use a foam roller on the lumbar spine.  This is because the diameter of the foam roller makes it very difficult for most people to control the position of the lower back and it will often increase the lordosis in the lower back.  In this excessive lordotic position, there is increased pressure on the vertebrae and discs. The muscles in the lumbar region can benefit from myofascial release but it is important to use a more suitable piece of equipment such as a tennis ball. (Images for this post were ‘borrowed’ from www.healthandcare.co.uk)

Researched By : Kátia C. Rowlands – Pilates Instructor & Personal Trainer – 082 513 4256

 

Feeding Aggression on Dogs

Alot of dog owners really love feeding time. Dogs know when feeding time is, and they are very demonstrative about how happy they are when feeding time comes around. While all dogs are happy about the prospect of being fed though, some dogs tend to behave quite aggressively once their food has been served. Some dogs growl if someone is too near them while they eat, worse still, some dogs go to the extent of snapping at anyone they perceive as “too close” while they are feeding. This type of aggression in dogs is quite common, but it should not go uncurbed, as it could deteriorate into other forms of aggression if simply left unchecked.

The key to checking such aggression early is in showing your dog who the boss is. You don’t need to actually punish your dog to get that message across. The best way to demonstrate you are the boss is by establishing a consistent feeding schedule. Feed your dog only at certain preset times, don’t deviate from your routine. Don’t feed your dog anything in between meals, and get the cooperation of other household members who interact with your dog. In the event that your dog is too full to eat during mealtime, don’t leave the food out, feed your pet again only at the next scheduled mealtime.

Establishing a rigid schedule will give your dog a clear picture of who dictates when and how much he or she eats. This is essential if you want to curb your dog’s aggression while eating. A second important thing to establish is the order of importance; always feed your dog after your family and not before. If your dog begs at the table, don’t allow him or her to be fed. Feed your dog after your family is finished eating. That way, the dog will understand his or her rank in terms of superiority in the house. This again will go a long way towards toning down your dog’s aggression.

Giving table scraps is never a good practice for many reasons: First of all, it’s unsanitary, your dog will probably end up taking the food away and trying to eat it somewhere else and wherever he or she does eat, it will be a mess after. Secondly, dog food is nutritionally balanced to be ideal for dogs, and scraps from the table will upset that balance. Third, it is disastrous from a behavioral standpoint, your dog will feel that you can be manipulated and this will upset your established schedule and undermine your credibility as the master. When feeding time does come around though, make sure that while training your dog, someone is there to watch him or her eat, this will also help drive home the point that people will not try to take away their food.

With young dogs the tips we’ve given should be enough to eventually eliminate this sort of aggression early. If however, you are trying to train an older dog, you may need to use and additional method: that of not giving the food all at once. Let your dog have a small amount, and when he or she finishes, give more, repeat until your dog has eaten the correct amount as prescribed by your vet, or the packaging of your dog food; that way your dog is more likely to deduce that you are a giver of food, not somebody who takes it away.

Aggression at feeding time is a primal instinct, after all, in the wild, dogs are largely predators, and their instinct is to defend their food against other predators. With patience and consistency though, your dog can be taught that he or she shouldn’t misbehave at feeding time.