Monday, 11 August 2014

SAD STATE OF INTERNATIONAL MEDICINE

MEDICAL CARE IN AN UNDERDEVELOPED COUNTRY: STORY OF IGNORANCE, GREED AND SUFFERING

MEDICAL CARE IN AN UNDERDEVELOPED COUNTRY
STORY OF IGNORANCE, GREED AND SUFFERING
Let us call this South East Asian country, Srivijaya. Charming people, wonderful smiles, tolerant of others, they had suffered greatly through colonial and postcolonial brutalities.
In the last 10 years, there has been unbridled, uncontrolled, ill charted growth and development, mired in corruption and non-transparency.
Infrastructure that allows the bourgeoisie and politicians to increase their wealth, in tandem with the total, wanton neglect of the welfare of the poor, who constitute the majority of the population.
Health care was totally neglected, and those who had a little income (average wages are below 100 USD per month) could see a doctor in private practice who may give injections or fluid therapy, at proportionately tremendous costs. Among those with access to money, they fly off to KL, Singapore or Bangkok for their medical care, without realizing that these places offer better technical medical care than is available in Srivijaya but not better humanitarian care. I am told of many stories of those who went off to Singapore or Bangkok, only to return with a slew of new medications and investigations that the local doctors couldn't follow through.
I give a case history of suffering but of successful outcome of a Srivijaya resident, thanks to my friends, Drs W and H, in Miami.
This 42-year-old man, who has been in perfect health, began noticing increasing fatigue and weight loss, towards the end of 2013. The city where he lived, which is very popular with western tourists, lacks easy access to medical care, except for a private hospital staffed by Australian doctors with a very bad reputation. He decided to go to the capital city where he was advised to see a Gastroenterologist, since his complaints were weight loss, vague abdominal pains and fatigue.
The Specialist physician carried out an Upper GI (stomach) and a lower GI (colon). As is the case with many people who are leading lives peppered with low fibre, high sugar food, the specialist found Gastritis and Diverticulosis. As he had noticed a high White Cell count, the specialist prescribed in addition to Proton Pump Inhibitors (Prevacid is the name of the medication in the USA) and also triple antibiotics for presumed Diverticulitis! My friend took these medications faithfully but found that at the end of the month, his symptoms had not improved. The specialist had requested some blood tests and once again it was noticed that the White Blood Cell counts were inappropriately elevated (close to ten times the normal). At that time, he got in touch with me through email and I talked to him on the telephone and I suspected that this did not sound like Diverticulitis but something more sinister in which faulty production of the White Blood Cells were involved. I encouraged him to go Bangkok for further investigations. He referred himself to a doctor in Bangkok (I do not have any medical contacts in Bangkok), who turned out to be a GI specialist, since my friend was thinking that the problems lay in his Gut, who repeated the endoscopic studies done in the capital city of Srivijaya, and proudly confirmed the diagnosis. But the concerned doctor noticed that the White Blood Cell count now exceeded over 100,000, abnormally high and referred the patient to a Haematologist, who admitted the patient to a hospital and within a day had the correct diagnosis, after a bone marrow biopsy.
My friend waited out the results in a hotel in Bangkok, only to be told that his condition was,
Chronic Myelogenous Leukaemia, with Ph+ positive, with BCR-CHL divergence of 90% (these are extremely sophisticated studies).
The haematologist prescribed Hydroxyurea as a stopgap measure to bring down the white blood cell count while waiting for the definitive treatment with expensive medications that were available in all the countries in South East Asia with the exception of Srivijaya. The doctor did give hope that if he were to take these medications on a regular basis, there is a high chance he would be cured.
I was in touch with him through this period on email and telephone. Surprise was in store for my friend when he enquired at the pharmacy about the medication prescribed for him, back in Srivijaya. He was told that they could procure the medication for him for $175 per pill! And the payment has to be in cash!
The price of the medication was similar in Singapore, Kuala Lumpur or Bangkok!
Like many busy administrators, he was not aware of the seriousness of his condition and once again we talked. He wondered whether he could just take Hydroxyurea and not worry about the new medication prescribed for him. He has been feeling better since he began taking it.
Right about this time, I had read about a court case in India, where a western pharmaceutical company had given up suing the government for breach of patent. The lifesaving medication, the name I couldn't remember was being distributed as a generic in India.
Once I had all the investigations, scanned to me, on hand, I contacted two good friends of mine in Miami, Drs W and H, one of whom is a professor of Haematology at the University of Miami.
Where could we get the life saving medication for our Srivijaya friend? A telephone call to a pharmacist in Bangalore in India gave us the breath of life, I clearly remember the relief I felt when the pharmacist told me that this medication is available in blisters of 10 for 1523 INR (about 25 dollars, i.e. $2.5 dollars each!), a fraction of the price in the pharmacies of the south east Asian nations! Thank you, India!
The name of the medication is Imatinib, 400 mg in strength, marketed as Gleevac in the USA.
Imatinib was invented in the late 1990s by scientists at Ciba-Geigy (which merged with Sandoz in 1996 to become Novartis), in a team led by biochemist Nicholas Lydon and that included Elisabeth Buchdunger and Jürg Zimmerman and its use to treat CML was driven by oncologist Brian Druker of Oregon Health & Science University (OHSU). Other major contributions to imatinib development were made by Carlo Gambacorti-Passerini, a physician scientist and hematologist at University of Milano Bicocca, Italy, John Goldman at Hammersmith Hospital in London, UK, and later on by Charles Sawyers of Memorial Sloan-Kettering Cancer Center. Druker led the clinical trials confirming its efficacy in CML

In 2013, more than 100 cancer specialists published a letter in Blood saying that the prices of many new cancer drugs, including imatinib, are so high that U.S. patients couldn't afford them, and that the level of prices, and profits, was so high as to be immoral. [They stated that in 2001, imatinib was priced at $30,000 a year, which was based on the price of interferon, then the standard treatment, and that at this price Novartis would have recouped its initial development costs in two years. They stated that after unexpectedly becoming a blockbuster, Novartis increased the price to $92,000 per year in 2012, with annual revenues of $4.7 billion. Other doctors have complained about the cost.
We were able to arrange the delivery of medications on a regular basis to Srivijaya at $40 per blister pack of 10 tablets. He gets 50 tablets at a time, delivered to him by air, he has never ran out of medications.
I made arrangements to visit him at Srivijaya in March 2014, adding a side trip to my visit to SE Asia. I reviewed his laboratory tests and was very pleased to see that the white cell count has steadily decreased and now hovered around 6000! 
Two months later (May 2014) the patient from Srivijaya got in touch with me again with a slew of questions.
How long do I have to take Imatinib?
When do I need another Bone Marrow Biopsy?
Should I go back to the doctor in Bangkok who did the bone marrow biopsy?
During the last week of May 2014, I had scheduled a visit to my good friend in Indonesia, the humble man of Bogor. American Indians say that things happen for a reason, and that we are not smart enough to decipher why most of the time! Few days before my appointed travel towards Singapore and Jakarta, my friend was summoned by the Ministry of Agriculture to be present at the meetings of visiting specialists, that would take him away from his home and work. Visiting him and his family and staff is one of my highlights of a visit to South East Asia. As I had already booked my tickets to Singapore, I decided to go to Srivijaya instead to visit and counsel my friend with CML who was taking Imatinib! I tried to visit a project I was involved in another country but the coordinator was out of the country during that period.
I had an uneventful flight from Havana. Havana-Miami-Newark-Hong Kong-Singapore. After arriving in Singapore at 12 30 AM, I was able to book a ticket to his city that very same morning.
It was as if I was supposed to be here, I had been there two months before. I spent time visiting friends, old and new. This visit was more than a social visit.
With the help of my friends in Miami, we were able to chart a course of treatment for him, with follow up tests to be carried out at regular intervals. Since there were no adult haematologists in all of Srivijaya, and the country does not have infrastructure to do the sophisticated blood tests (called FISH), we found out that it is possible to get the tests done in Ho Chi Minh City in Vietnam! His Family Practitioner in Srivijaya was a retired French doctor who confessed that he knew nothing about his illness. I left Srivijaya leaving detailed instructions for him for follow up (as given by my friend in Miami). And to find a concerned and interested Family Practitioner in his town!
Dr H was head of Haematology as well as Internal Medicine at the University of Miami/Jackson Memorial Hospital when I was a student there. His dedication to International medicine was exemplary, and I was influenced by it. I had a chance to work with him a little, organizing a connection to Jamaica.
The doctor friend who helped me in Miami was none other than the son of the above professor!
I sat down on banks of the river not too far from the river and offered a prayer of gratitude. I felt so humble and elevated in spirit, that I had to hold back my tears!
A Kaddish for all my illustrious teachers: Dr H, Haematology, Dr L, Oncology, Dr R, Endocrinology all from University of Miami and Dr H, Medical Anthropology from London

Just this morning, I received eCopy of NEJM for July 3, 2014
There is an article on Putting quality on the Global Health Agenda
from Harvard University. An Interesting article. I would just quote one line from it.
In a study involving standardized patients in INDIA, nearly 7 out of 10 medical providers failed to ascertain the basic pertinent history for common ailments such as angina, asthma, and childhood diarrhea and incorrectly diagnosed a large majority of cases!

Monday, 9 June 2014

OLIVE OIL AND SALAD COMBINED MAY EXPLAIN THE MEDITERRANEAN DIET SUCCESS

Olive oil and salad combined 'explain' Med diet success


The combination of olive oil and leafy salad or vegetables is what gives the Mediterranean diet its healthy edge, say scientists.
When these two food groups come together they form nitro fatty acids which lower blood pressure, they told PNAS journal.
The unsaturated fat in olive oil joins forces with the nitrite in the vegetables, the study of mice suggests.
Nuts and avocados along with vegetables should work too, they say.
Inspired by traditional cuisine of countries such as Greece, Spain and Italy, the Mediterranean diet has long been associated with good health and fit hearts.
Typically, it consists of an abundance of vegetables, fresh fruit, wholegrain cereals, olive oil and nuts, as well as poultry and fish, rather than lots of red meat and butter or animal fats.
While each component of the Mediterranean diet has obvious nutritional benefits, researchers have been puzzled about what precisely makes the diet as a whole so healthy.
Chemical reaction
Prof Philip Eaton, from King's College London, and colleagues from the University of California in the US believe it is the fusion of the diet's ingredients that make nitro fatty acids.
In their study, part-funded by the British Heart Foundation, the researchers used genetically engineered mice to see what impact nitro fatty acids had on the body.
Nitro fatty acids helped lower blood pressure by blocking an enzyme called epoxide hydrolase.
Prof Eaton said: "Humans have this same enzyme so we think the same happens in people."
This explains why a Mediterranean diet is healthy, even though it contains fat, he says.
"With the fats in the Med diet, if taken together with nitrates or nitrites, there's a chemical reaction and these combine to form nitro fatty acids.
"It's nature's protective mechanism. If we can tap into this we could make new drugs for treating high blood pressure and preventing heart disease," he said.
He said human trials were planned.
Dr Sanjay Thakrar of the British Heart Foundation said: "This interesting study goes some way to explain why a Mediterranean diet appears to be good for your heart health. The results showed a way in which a particular compound could combat high blood pressure, which is a major risk factor for heart disease.
"However, more work is necessary as these experiments were conducted in mice and this compound could also be having its effect through other pathways."

BAD SLEEP ALTERS THE BADY DRAMATICALLY

Bad sleep 'dramatically' alters body


A run of poor sleep can have a potentially profound effect on the internal workings of the human body, say UK researchers.
The activity of hundreds of genes was altered when people's sleep was cut to less than six hours a day for a week.
Writing in the journal PNAS, the researchers said the results helped explain how poor sleep damaged health.
Heart disease, diabetes, obesity and poor brain function have all been linked to substandard sleep.
What missing hours in bed actually does to alter health, however, is unknown.
So researchers at the University of Surrey analysed the blood of 26 people after they had had plenty of sleep, up to 10 hours each night for a week, and compared the results with samples after a week of fewer than six hours a night.
More than 700 genes were altered by the shift. Each contains the instructions for building a protein, so those that became more active produced more proteins - changing the chemistry of the body.
Meanwhile the natural body clock was disturbed - some genes naturally wax and wane in activity through the day, but this effect was dulled by sleep deprivation.
Prof Colin Smith, from the University of Surrey, told the BBC: "There was quite a dramatic change in activity in many different kinds of genes."
Areas such as the immune system and how the body responds to damage and stress were affected.
Prof Smith added: "Clearly sleep is critical to rebuilding the body and maintaining a functional state, all kinds of damage appear to occur - hinting at what may lead to ill health.
"If we can't actually replenish and replace new cells, then that's going to lead to degenerative diseases."
He said many people may be even more sleep deprived in their daily lives than those in the study - suggesting these changes may be common.
Dr Akhilesh Reddy, a specialist in the body clock at the University of Cambridge, said the study was "interesting".
He said the key findings were the effects on inflammation and the immune system as it was possible to see a link between those effects and health problems such as diabetes.
The findings also tie into research attempting to do away with sleep, such as by finding a drug that could eliminate the effects of sleep deprivation.
Dr Reddy said: "We don't know what the switch is that causes all these changes, but theoretically if you could switch it on or off, you might be able to get away without sleep.
"But my feeling is that sleep is fundamentally important to regenerating all cells."

Friday, 21 February 2014

STRENGTH TRAINING FOR CHILDREN AND ADOLESCENTS : BENEFITS AND RISKS

Coll. Antropol. 37 (2013) Suppl. 2: 219–225
Review
Strength Training for Children and Adolescents:
Benefits and Risks
Davide Barbieri and Luciana Zaccagni
University of Ferrara, Department of Biomedical and Specialty Surgical Sciences, Ferrara, Italy
A B S T R A C T
Physical activity has proved to be an effective means of preventing several diseases and improving general health. In
most cases, though, light to moderate efforts are suggested, for both youngsters and adults. Common sense advices call
for late inception of intense, strength training-related activities, like weight lifting and plyometrics, which are usually
postponed at the end of the growth age, even among sport practitioners. However, such advices seem to have a mainly anecdotal
nature. The purpose of this review is to evaluate risks and benefits of early inception of strength training, at adolescence
or even earlier, and to verify whether concerns can be grounded scientifically. Current literature does not seem to
have any particular aversion against the practice of strength training by children and adolescents, provided that some
safety rules are followed, like medical clearance, proper instruction from a qualified professional and progressive overload.
At the same time, several studies provide consistent findings supporting the benefits of repeated, intense physical efforts
in young subjects. Improved motor skills and body composition, in terms of increased fat free mass, reduced fat
mass and enhanced bone health, have been extensively documented, especially if sport practice began early, when the subjects
were pubescent. It can be therefore concluded that strength training is a relatively safe and healthy practice for children
and adolescents.
Key words: strength training, weight lifting, adolescents, growth, body composition
Introduction
Modern Western societies imply increasingly sedentary
life styles and reduced physical exercise. Technological
progress, limited outdoor activities and economic improvement
have modified dietary habits and reduced the
amount of exercise performed by children and adolescents1.
It is well known that regular moderate intensity
physical activity – such as walking, cycling, or participating
in sports – has significant benefits for health. According
to the 2008 guidelines of the European Commission2,
school-aged youth should participate in moderate to vigorous
daily physical activity for 60 minutes or more. Obesity,
sedentary lifestyle and poor cardio-respiratory fitness
in childhood and adolescence may increase the risk
of health problems later in life. The teenage years bring
many physical, social and psychological changes for the
individual. From infancy to adulthood, growth, maturation
and development occur simultaneously and interact:
growth consists in the increase of the size of the body as a
whole and of its parts, maturation refers to progress towards
the biologically mature state and development refers
to the acquisition of behavioral competence3.
Changes in body dimensions and composition during
growth and maturation are factors affecting strength
and motor performance4. Some changes in anthropometric
traits and strength in a sample of Italian adolescents
studied by Gualdi-Russo and Toselli5 are reported in Figures
1–4.
The strength and motor performance varies during
childhood and adolescence in relation to biological and
environmental factors. Among biological factors the specific
contribution of maturity status is apparent: the
strength advantage of early-maturing subjects is related
to their larger body size in comparison to late-maturing
ones. These differences are more marked in boys than in
girls. Regular physical activity is an important factor
during growth and maturation, regulating body weight
and, particularly, fatness.
219
Received for publication October 15, 2011

Strength Training: Concepts and Objectives
Strength training is a form of physical activity, usually
structured and planned, involving intense efforts
against a resistance. Its main aim is to increase muscular
strength, in order to improve performance, at least in
case a sport is practiced. It is extensively adopted in
power-oriented sports, like sprinting6 and soccer7, even if
its benefits are recognized also in endurance sports, like
long distance running8,9 and cross country skiing10,11. In
a non-competitive environment instead, strength training
is adopted for many different purposes. For example,
strength training may be used to improve overall fitness,
increasing muscle hypertrophy and reducing body fatness
at the same time. In fact, strength training can be
an effective means to improve body composition12. In
other cases, some individuals may adopt it in order to accomplish
some professional goal, like achieving the degree
of physical fitness which is required in the military
or to join the fire brigade.
To train strength, muscular force is applied against
some kind of resistance. In most cases, especially when
the individual is healthy, resistance is provided by free
weights, like barbells, dumbbells or the athlete’s own
body weight, or by weight machines, like the leg press,
the lat machine etc. This kind of training is usually
adopted in sport conditioning, because the load can be increased
progressively according to the athlete’s strength,
which can be considerable. Athletes employ gravity also
in other ways in order to improve their performances,
like in plyometrics or high-impact training, where body
mass is accelerated dropping from a pre-determined
height, according to the athlete’s ability and conditioning
level. This kind of strength training is usually considered
the most dangerous, because the real impact forces applied
to the athlete’s body (bones, muscles, tendons, ligaments
etc.) are not easily measured, as in weight lifting.
Since force is defined as mass times acceleration, we can
say that weights mainly focus on the first factor, while
plyometrics relies on the second to increase force. Nonetheless,
also weights can be accelerated, in order to increase
force production without adding kilograms, and
advanced plyometrics may imply added weight by means
of weighted belts or vests.
It must be considered, though, that similar strength
training effects can be found in sport practices other
than weight lifting or plyometrics, like sprinting, gymnastics
and other kinds of power-oriented sports, or team
sports involving leaping and bouncing, like volleyball and
basketball. These types of physical efforts produce great
acceleration, which, applied to the athlete’s body mass,
produce great force. Nonetheless, these intense efforts
are usually practiced by children, even outside a sport
environment, simply while playing with their peers.
Strength training has in important role in rehabilitation
after injuries, especially those which involve surgery
and/or a long period of immobilization, in order to re-gain
the physiological muscle hypertrophy and joint range of
motion13–18. In case of injuries to lower limbs, when the
patient is still lying in bed, body weight can be excessive
and not suitable for post-surgery rehabilitation. Therefore,
non-bodyweight bearing exercises can be used, by
means of cables and/or small weights, attached to the ankles
of the patient, like in leg raises and knee extensions.
Body weight can be excessive also for healthy individuals
who have a low relative strength, that is a low
strength-to-body weight ratio. A push up, a pull up or
even a body weight squat can be a demanding task for
people who are too young, elderly, overweight or out of
shape. Free weights or machines can provide a controlled
and adjustable source of resistance. For example, a push
up can be effectively substituted by a bench press, a pull
up by a lat pull down using a lat machine, a body weight
squat by a leg press, involving more or less the same
muscle groups. Weights can be adapted to the individuals’
actual strength, which may be relatively low compared
to their own body weight.
Other kinds of resistance than weights may be applied
in order to increase muscular strength, like elastic
bands, or friction, as in water or on a steady bike. In fact,
gravity is not necessarily present (e.g. astronauts during
space missions are at risk of losing considerable amounts
of muscle mass19,20) or not fully applicable. Orthopedics
patients may have access to a swimming pool, where the
weight-bearing effort of an injured knee, ankle or hip can
be reduced. At the same time, also competitive swimmers
may use swim paddles to increase the resistance provided
by water.
Exercises are usually performed in sets of several repetitions
(i.e. consecutive lifts). If heavy loads are employed,
providing stimulus for maximal strength, then
repetitions are necessarily low in numbers. When the
load is moderate, in order to improve body composition
and cardiovascular fitness, then the overall number of
repetitions can be considerably high. The main training
parameters are intensity and volume. Intensity is given
as percentage of the maximal load which can be lifted for
the prescribed number of repetitions: 1 repetition-maximum
(RM) is the load which can be lifted just once, 10
RM is the load which can be lifted 10 times within one
set. Strength training implies relatively heavy loads, between
60% and 100% of 1 RM, the so-called »strength
training zone«21. For example, the 90% of 1 RM is a quasi
maximal load, allowing for small volume (i.e. low repetitions).
Volume is the total number of repetitions per exercise.
For example, performing 3 sets of 10 repetitions in
one given exercise determines a volume of 30 repetitions.
D. Barbieri and L. Zaccagni: Resistance Training before and during Adolescence, Coll. Antropol. 37 (2013) Suppl. 2: 219–225
221
The most common strength training exercises are
listed in Table 1, with the discipline in which they are
usually practiced, even if in most cases athletes involved
in different sports may use a blend of them. This is especially
true in body building, where the overall balanced
development of muscle mass is of great importance.
Therefore, body builders use most of the listed exercises
(and even more than those), while strength training for
athletes usually comprises a small set of exercises, like
the clean, the squat and the bench press, involving most
skeletal muscles in a coordinated fashion.
Benefits and Risks of Strength Training
for Children and Adolescents
For reasons which have been mainly reported anecdotally,
strength training, especially if involving weight
lifting, has been considered dangerous for children and
adolescents, and at risk of limiting their growth. However,
the American College of Sports Medicine highlights
that there is no current scientific evidence of the fact
that strength training and weight lifting are inherently
dangerous or can restrain the growth of children and adolescents.
Like any other kind of sport practice, there are
some risks which can be considerably diminished following
a small set of suggestions: proper supervision form
an expert adult, warm up and stretching before lifting,
focus on proper form rather than load, gradual resistance
increases as technique, strength and control improve22.
The American Academy of Pediatrics gives comparable
guidelines, implying that strength training can be
safe and effective for children and adolescents, provided
that medical clearance is granted. At the same time, it
discourages them from practicing sports, like Olympic
weightlifting and powerlifting, which involve maximal
lifts23–25.
A similar position has been taken by the National
Strength and Conditioning Association, which is in favor
of supervised and appropriately prescribed strength
training for both pre-adolescents and adolescents26.
In strength training, the gains in muscular strength
are often associated with improvements in body composition.
In a study by Faigenbuam et al.27 a group of boys
and girls aged between 8 and 12 followed a twice-a-week
resistance training program for 8 weeks. After warm up
and stretching, the training group performed the following
5 exercises: leg extension, leg curl, bench press, overhead
press and biceps curl. Both training and control
groups continued physical education at school. As expected,
strength gains in the training group were significant
compared to both pre-training and control. Also improvements
in body composition were significant:
skinfold thickness decreased of 2.3% on average, compared
to an increase of 1.7% in control group. It is interesting
to note that upper arm, chest and hip girths did
not change significantly. The only exception was the
thigh girth, which anyway increased relatively less than
control (+2.4% vs. +3.9%).
The volume-intensity schema adopted was the popular
Delorme method: 3 sets of 10 repetitions each, the
first one with 50% of 10 RM, the second one with 75% of
10 RM and the third one with 100% of 10 RM. Delorme
was among the first physicians who realized the importance
of strength training – and weight lifting in particular
– in rehabilitation after injuries28.
A similar pyramiding method was adopted in a study
by Schwingshandl et al.29. Obese children and adolescents
were prescribed a diet with caloric restriction. Unfortunately,
diet alone may reduce both fat and fat free
mass. Subjects were therefore divided into 2 groups:
training and control. After some light aerobics and stretching
as a warm up, the training group performed 3 to 4
sets, 10 repetitions each, of the prescribed exercises,
which were chosen to involve all major muscle groups.
The first set was performed using the 50% of 10 RM.
Load was increased progressively in each set, until muscle
failure because of fatigue. When the child was able to
complete more than the prescribed 10 repetitions in the
last set, the load was increased in the following training
session. After 12 weeks, weight change was not significant
in both groups, while the increase in fat free mass
was significantly higher in the training group than in
control, implying that resistance training may have a
positive effect on body composition in fat reduction programs
for obese children and adolescents.
Supervised strength training, involving weight lifting
(bench press, leg extension, lat pull down etc.) and stretching,
after an adequate warm up, has proved to be effective
in a group of children, males and females, increasing
strength, reducing skinfold thickness, improving
body composition, motor skills and flexibility30.
In a study by Watts et al.31 obese adolescents were involved
for 8 weeks in a strength training program consisting
in 1 hour of circuit training, 3 times per week, including
both cycle ergometer and resistance training.
Since the program was primarily designed to treat obesity
rather than improving strength, exercise intensity
was kept between 55–70% of pre-training 1 RM. Training
reduced abdominal and trunk fat, thus diminishing cardiovascular
and metabolic risks, and increased strength,
body composition and overall fitness at the same time.
Even if the main purpose of strength training is to increase
muscle strength, it seems to have a positive carry
D. Barbieri and L. Zaccagni: Resistance Training before and during Adolescence, Coll. Antropol. 37 (2013) Suppl. 2: 219–225
222
TABLE 1
COMMON STRENGTH TRAINING EXERCISES
Olympic
weightlifting
Powerlifting Body
building
Body weight
training
Snatch
Clean and
jerk
Squat
Bench press
Deadlift
Overhead
presses
Biceps curls
Leg extensions
Leg curls
Rowers
Push ups
Pull ups
Parallel dips
Body weight
squats
One-leg squats
Sit ups
over also in bone density and therefore it qualifies as an
interesting means for preventing and reducing osteoporosis.
This is particularly true for children: if strength
training is adopted early, bone mass gains last longer.
Skeletal exposure to mechanical loading during growth
seems to be an effective strategy to increase bone mass
and density, according to Khan et al.32. In a study by
Fuchs et al.33, high impact training is used to verify its efficacy
in improving skeletal mass in a group of elementary
school children. Bone mineral content, bone area
and bone mineral density were adopted as indices of bone
health. The training protocol consisted in 100 drop
jumps form a 61 cm box, 3 times per week for 7 months,
implying ground reaction forces up to 8 times body
weight. However, the adopted method proved to be safe
and effective in improving the above mentioned parameters
at the femoral neck and lumbar spine. Actually, in a
popular sport like gymnastics, impact forces in drop
landings range from 8.2 to 11.6 times body weight, according
to a study by Ozguven and Berme34.
Even if the authors say that the program could be introduced
in physical education classes, its main limitation
may be in the fact that high-impact training may result
in an excessive effort for overweight children. Still,
in the training group no injuries occurred during the
whole duration of the study. Actually, selected children
had to be within the 20% of the recommended weight for
height and age. The benefits at the femoral neck persisted
even after several months of detraining, when the
same bone health parameters were re-assessed in both
exercise and control group35.
Significant positive effects of impact training on bone
mineral content at the hip was also found by Gunter et
al.36 in a longitudinal study. The benefits of 7 months of
impact training on a group of school children were partially
maintained up to 8 years later.
Osteoporosis is a major problem especially for adult
women. Even if considerable improvements in terms of
bone health can be assessed in adults engaging in some
form of strength training, the benefits do not seem to
persist as long as in children or adolescents, suggesting
that early inception of intense physical exercise may be
prescribed for long-lasting improvements. A study by
Winters and Snow37 assessed bone mineral density in a
group of females aged 30–45, before and after a 12 month
training period. The training program included both
high impact and resistance training (squats, lunges and
calf raises). Drop jumps off a box generated ground reaction
forces of 4 to 5 times body weight. Intensity was
gradually increased using weighted vests. After the training
period, exercisers improved their bone mineral density
and strength significantly, with respect to both baseline
(pre-training) and control values. Unfortunately
though, after 6 months of detraining, values decreased
significantly towards baseline values.
A study by Kannus et al.38 evaluated the effects of
playing starting age on bone mineral content of the dominant
arm in a group of female tennis players. Athletes
had a significantly higher difference in bone mineral content
between dominant and non-dominant arm compared
to control. The difference was 2 to 4 times greater
in individuals who had started playing tennis before or at
menarche, compared to those who had started 15 years
after menarche. Tennis resembles strength training and
may carry over similar effects on the bones since it consists
of ballistic and explosive movements, handling a
light implement. Even if the involved masses are small
(ball and racquet), the acceleration produced during the
impact may be very large, producing great force against
the dominant arm.
Similar positive effects on bone mineral density of female
gymnasts were found by Proctor et al.39 in the
whole body and in particular in the upper limbs, without
any significant bilateral differences, which is a major advantage
compared to tennis. Gymnastics exercises, like
pull ups and ring or parallel dips, are often employed in
body weight strength training, for their carry over to upper
body muscle strength.
Swimming and cycling are among the most popular
sports and bring several health benefits. However, bones
seem to be less directly addressed by these activities, because
of their non-weight-bearing nature, which limits
the loading on the skeleton. A group of well trained adolescent
females (track and field athletes, gymnasts and
water polo players) were assessed by Greene et al.40. Although
all the selected sports require intense physical
work, gymnastics involves weight-bearing in both the upper
and lower body, track-and-field (sprints and jumps)
only in the lower body, and water polo has no weight-
-bearing component. Water polo players did not show
greater bone strength or muscle size in the lower leg
compared to controls. On the contrary, gymnasts showed
significantly greater bone strength than non active females.
Also track-and-field athletes displayed greater
bone strength in the lower leg, compared to controls. The
gymnasts showed the greatest musculoskeletal benefits
in the upper body. Despite intense training, water polo
players showed no significant benefits in musculoskeletal
health in the lower body and only limited benefits in
the upper body when compared with non active girls.
Ferry et al.41 investigated bone mineral density in female
adolescent soccer players, swimmers and control
group. Bone mineral density was significantly higher in
soccer players compared with swimmers. In contrast,
swimmers had weaker bones than controls, despite the
fact that female swimmers cannot be considered sedentary
subjects.
Effects of strength training on connective tissues (ligaments
and tendons in particular) have not been as
widely assessed as those on bones. However, a recent
study42 has found a positive correlation between resistance
training (in particular Olympic weightlifting) and
cruciate ligaments’ cross sectional areas. The authors
conclusions are that the benefits were induced by early
inception of heavy training at the age of puberty.
D. Barbieri and L. Zaccagni: Resistance Training before and during Adolescence, Coll. Antropol. 37 (2013) Suppl. 2: 219–225
223
Discussion and Conclusions
An meaningful distinction should be made between
weight lifting for strength training and Olympic weightlifting.
The latter implies competitions in which maximal
or even supra-maximal (when the lift fails) loads are employed,
as in powerlifting. In strength training instead,
sub-maximal weights, which can be lifted more than
once, are used. This distinction may account for a different
risk factor between the aforementioned disciplines.
In general, whenever a maximal effort is required, as in
competitive sport, it is believed that risks tend to be present
in a higher percentage than in recreational activities.
More specifically, even if strength training may be strenuous
and intense, if no maximal loads are employed, than
it can be considered a safe and effective form of physical
activity for most individuals, including children and adolescents,
provided that proper instruction and supervision
are given.
However, a study by Hamill43 questions the common
belief that resistance training is safer than Olympic
weightlifting, since both appear to be relatively safe according
to his findings, especially if compared to other
sports. The surveyed subjects were UK students, aged 13
to 16. Practicing both Olympic weightlifting and weight
training had an injury rate of only 0.0012 per 100 participation
hours. Individually, both disciplines scored well
below other popular British sports, like soccer, rugby or
even athletics.
In a study by Risser et al.44 muscle strain, a non-disabling
injury, was reported to be the most common accident
among high school American football players practicing
weight lifting as a form of strength training. The
cumulative percentage of injuries among all athletes was
a reasonable 7.6%, corresponding to 0.082 injuries per
person/year. Much higher rates can be found in adolescent45
or amateur46 soccer players. However, the study
did not specify whether injuries were caused by maximal
lifts (i.e. excessive load) or poor form, as it may happen in
a competitive environment, where fatigue and strive for
performance may lead to an excessive demand on the
athlete's physical capabilities.
The topic of growth and strength training could be
further assessed from an endocrine point of view, considering
the relationship between exercise and hormonal responses.
A review by Kraemer and Ratamess47 highlights
the well established finding that resistance training and
growth hormone are positively correlated, but further research
is needed in order to verify whether strength
training could induce positive endocrine responses in adolescents.
In conclusion, early inception of strength training, at
adolescence or even earlier, does not seem to imply higher
risks than other popular sport disciplines, provided
that the young athletes follow the aforementioned guidelines.
In particular, supervision by an expert instructor,
focus on proper technique and cautious progression in increasing
loads are the most common advices which must
be adhered to. On the positive side, resistance training
has proved to increase basic motor skills, like muscle
strength, coordination and flexibility, but also body composition,
in terms of improved fat free to fat mass ratio
and increased bone health.