10-20-30 Training

Jens Bangsbo and Thomas Gunnarsson from the University of Copenhagen have published the results (Journal of Applied Physiology) of a fascinating study comparing the effects of interval training to regular endurance training. A group of moderately trained runners was split into 2 groups: over a 7-week period the control group continued their normal runs and the interval group replaced their usual runs with the 10-20-30 protocol.

The 10-20-30 protocol consisted of a 1km warm-up followed by 3-4 5 min blocks of interval training. Each block was followed by 2 min of recovery. The interval training was made of low, moderate and high-speed running (<30%, <60% and >90% of maximal intensity) for 30, 20 and 10 sec respectively.

Although the total training volume in the interval group was less than half that of the control group (14 km/week vs 30 km/week), it produced some amazing results. At the end of the study, the 10-20-30 group increased their VO2 max (maximal oxygen consumption) by 4% and improved their 1500 m and 5 km runs by 21 sec and 48 sec respectively. In addition to this, they significantly decreased their systolic blood pressure, total cholesterol and LDL cholesterol levels.

So despite a 50% reduction in training volume, 10-20-30 interval training improves the performance and health of trained runners.

Pain: how much is in the mind?

A study by Luis Buenaver and colleagues published in the June edition of Pain has shown some fascinating links between pain, thinking and sleep. It’s already known that about 80% of people with chronic pain experience troubled sleep and that poor sleep increases pain sensitivity. It is also known that pain catastrophizing is a contributor to chronic pain. Catastrophizing is a combination of rumination and negative thinking. What Buenaver and his colleagues discovered was a direct link between pain catastrophizing, poor sleep and worsening pain…a vicious cycle…the more often you think negatively about your pain experience…the more your sleep is disrupted…the worse your pain becomes…which in turn adversely affects your thoughts, etc.

Another piece of research published in this month’s Current Biology by Christian Sprenger et al. demonstrates that mental distraction techniques can decrease pain sensations by inhibiting incoming pain signals in the spinal cord. The effect was found to be partly mediated by endorphins.

In essence, people with chronic pain can improve their sleep and comfort by choosing to focus on pleasant activities or goals rather than brood gloomily over their pain.

To change the way we feel we must change the way we think!

Acupuncture May Prevent Muscle Wasting

A study by Akiko Onda et al. published in Biochemical and Biophysical Research Communications has concluded that “acupuncture can partially prevent skeletal muscle atrophy”. It helps recover skeletal muscle mass and cross-sectional area possibly by increasing protein synthesis and decreasing protein degradation. Although the experiment was performed on mice, it was hypothesised that acupuncture could be used to prevent muscle wasting in the elderly and in patients with “severe conditions”.

Lighter Weights Also Help Muscle Growth

Exciting new research by Burd and colleagues shatters currently held beliefs about the type of resistance training required for muscle growth. Their article entitled “Bigger weights may not beget bigger muscles: evidence from acute muscle protein synthetic responses after resistance exercise” has been published in the journal Applied Physiology, Nutrition, and Metabolism. They found that performing repetitions until fatigue (an average of 24 repetitions) with 30% of one repetition maximum (1RM) was just as effective at eliciting muscle protein synthesis (MPS) as 5 repetitions with 90% 1RM! In fact, exercise performed at 30% 1RM produced longer lasting MPS.

The authors believe that maximal muscle fibre recruitment is fundamental in inducing MPS and that lifting light weights to failure causes the fibre activation required. In addition, low-intensity resistance exercise allows for a higher total number of repetitions and greater total exercise volume, which is important in sustaining the MPS response over time.

Burd et al. note that “skeletal muscle mass is a large contributor to daily energy expenditure and will assist in weight management. Additionally, skeletal muscle, because of its overall size, is the primary site of blood glucose disposal and thus will likely play a role in reducing the risk for the development of type II diabetes”.

Steroid Epidurals Can Help Relieve Sciatica

A recent randomised trial published in Annals of Internal Medicine by Cohen and his colleagues shows that steroid epidurals can help relieve sciatica. They found that “75% of patients treated with epidural steroids reported 50% or greater leg pain relief and a positive global perceived effect at 1 month”.  Of course, an epidural is an invasive treatment with associated risks and would probably not be the first choice of treatment. Conservative therapies such as physiotherapy, osteopathy, chiropractic, acupuncture, etc. should be the first port of call. In addition, your GP may prescribe anti-inflammatories and analgesia. Only in cases of severe sciatica when conservative treatment has not been effective should an epidural be envisaged.

Over time the healing process should help settle the sciatica, irrespective of whether or not a steroid epidural is performed, but an epidural can catalyse the process by decreasing pain, decreasing anxiety and stress, increasing mobility and allowing the participation in physiotherapy and rehabilitation.

Skiing And Snowboarding Injuries

A study by Suezie Kim et al. published in The American Journal of Sports Medicine has shown that injury rates in snowboarders are slightly higher than injury rates in alpine skiers. Snowboarders more commonly injure their wrists, shoulders and ankles while skiers tend to injure their knees.

In skiers the knee accounts for a third of all injuries but female skiers are twice as likely to injure their knees as men and 3 times as likely to strain their anterior cruciate ligaments (ACL). Gerhard Ruedl et al. found that women “showed a 2-fold higher risk of suffering an ACL rupture of their non-dominant leg”. Men had an equal chance of injuring the right or left knee. Ruedl told Reuters Health that women showed greater discrepancies in strength and proprioception (sense of joint positioning)  between their dominant and non-dominant legs. Most female skiers injured their left (non-dominant) ACLs during right turns when the forces on the left (outside) leg were greatest.

Shift Work May Cause Obesity And Diabetes

An article in today’s BBC News Health discusses recent research published in Science Translational Medicine. Dr Orfeu Buxton et al. have shown that “prolonged sleep restriction with concurrent circadian disruption alters metabolism and could increase the risk of obesity and diabetes”. This has implications to people performing shift work.

Sitting And Mortality

A few days ago the Archives of Internal Medicine published the timely results of the effects of sitting on mortality rates. van der Ploeg and her colleagues followed over 220,000 Australians over a 3 year period. The subjects were 45 years or older and sadly 5405 people passed away during the course of the study. The researchers found that mortality risks increased with daily sitting time. Compared to people who sat less than 4 hours a day, those that sat for 4-8 hrs had a 2% increased risk of mortality. Whereas those that sat for 8-11 hrs a day increased their risk by 15% and the subjects that sat for over 11 hrs increased their risk of death by a whopping 40%!

Fascinatingly, their results revealed that prolonged sitting was a risk factor for mortality independent of physical activity. Probably because “time spent doing moderate or vigorous exercise and time being totally sedentary may affect long-term disease risks separately.”

Don’t be too depressed about it…we all have to go at some stage…but if you prefer to leave later rather than sooner, have a look at my previous post ‘I Wouldn’t Sit For That (Part 2)‘ for some helpful tips!

Prolonged Sitting Affects Glucose Metabolism

New research published in the journal Diabetes Care has concluded that after meals, regular short bouts of light or moderate walking lower glucose and insulin levels. The subjects were asked to walk around for 2 mins every 20 mins. The effects of these short bouts of walking assist glucose metabolism and may reduce cardiovascular risk.

This adds to the mounting evidence regarding the health risks associated with prolonged sitting.

Meditation Increases Blood Flow To The Brain

Recent research has shown that mantra-based meditation increases cerebral blood flow. An improvement in attention, emotional state and memory was also noted. Therefore, it’s likely that people with cognitive impairments or memory loss will benefit from meditation.