Category: Recovery strategies

New systematic review and meta-analysis

I realised I have not written much on this blog since our activities started at Aspire Academy. This is clearly a sign that we have been very busy at work but also that the only time I had to write it has been spent writing scientific work. As a department we are doing very well not only because our service provision improves on a daily basis but also because we are starting to produce a lot of applied scientific papers which I hope can help the coaching and sports science community Worldwide in improving the support to athletes. We have quite a good number of articles already published, a few in press and many submitted which means that by the end of 2015 we might be able to make a significant contribution to our willingness to learn more and share the learning.

The most recent effort is an extensive systematic review and meta-analysis on the topic of cold baths in adolescent athletes. This was triggered by the fact that many coaches and sports scientists working with young athletes tend to replicate processes and procedures observed in senior athletes without questioning appropriateness and effectiveness. Our conclusions are pretty clear: there is no evidence of benefits of such interventions in adolescent athletes and there are a lot of unanswered questions when it comes to the implications for such recovery practice to negatively affect training adaptations. So as usual, there is a need for more and better studies to understand this with all the limitations of conducting studies in a youth population.

The article is free and completely accessible online. The abstract is below.
If you are interested in reading it, just click here and download the PDF.

Abstract

Recovery and regeneration modalities have been developed empirically over the years to help and support training programmes aimed at maximizing athletic performance. Professional athletes undergo numerous training sessions, characterized by differing modalities of varying volumes and intensities, with the aim of physiological adaptation leading to improved performance. Scientific support to athletes focuses on improving the chances of a training programme producing the largest adaptive response. In competition it is mainly targeted at maximizing the chances of optimal performance and recovery when high performance levels are required repeatedly in quick succession (e.g. heats/finals). In recent years, a lot of emphasis has been put on recovery modalities. In particular, emphasis has been placed on the need to reduce the delayed onset of muscle soreness (DOMS) typically evident following training and competitive activities inducing a certain degree of muscle damage. One of the most used recovery modalities consists of cold-water immersion and/or ice/cold applications to muscles affected by DOMS. While the scientific literature has provided a rationale for such modalities to reduce pain in athletes and recreationally active adults, it is doubtful if this rationale is appropriate to aid training with adolescent athletes. In particular, since these methods have been suggested to potentially impair the muscle remodeling process leading to muscle hypertrophy. While this debate is still active in the literature, many coaches adopt such practices in youth populations, simply transferring what they see in elite sportspeople directly; without questioning the rationale, safety or effectiveness as well as the potential for such activity to reduce the adaptive potential of skeletal muscle remodeling in adolescent athletes. The aim of this review was to assess the current knowledge base on the use of ice/cold applications for recovery purposes in adolescent athletes in order to provide useful guidelines for sports scientists, medical practitioners, physiotherapists and coaches working with such populations as well as developing research questions for further research activities in this area. Based on the current evidence, it seems clear that evidence for acute benefits of such interventions are scarce and more work is needed to ascertain the physiological implications on a pre or peri-pubertal population.
Keywords: 

Recovery; Ice; Cold; Youth; Adolescent; Athlete; Elite

>Sleep and teenagers

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Sleep (or lack of…) is an interesting topic. Quality of sleep has been shown to negatively affect human performance for various reasons. Furthermore, there have been numerous reports suggesting a link between lack of sleep and depression.

The relationship between short sleep duration and depression has been suggested to be bidirectional,1 with chronic partial sleep deprivation being a potential risk factor for depression. Cross-sectional studies have found relationships between inadequate sleep and depression in adolescents,2,3 and a longitudinal study has shown that getting less sleep over time increased the symptoms of depression among middle school students.4 Short sleep duration has also been shown to be associated with suicidal ideation5 and suicidal behavior6 in adolescents and adults7 in cross-sectional studies.

A recent quasi-experimental study conducted by Gangwish et al. (2010) has looked at the relationships between parental set bedtimes, sleep duration, and depression in adolescents to explore the potentially bidirectional relationship between short sleep duration and depression.

For this scope they analysed 15,659 US adolescents in grades 7 to 12. The results showed that adolescents with parental set bedtimes of midnight or later were 24% more likely to suffer from depression (OR = 1.24, 95% CI 1.04-1.49) and 20% more likely to have suicidal ideation (1.20, 1.01-1.41) than adolescents with parental set bedtimes of 10:00 PM or earlier, after controlling for covariates. Consistent with sleep duration and perception of getting enough sleep acting as mediators, the inclusion of these variables in the multivariate models appreciably attenuated the associations for depression (1.07, 0.88-1.30) and suicidal ideation (1.09, 0.92-1.29).

From Table 3
Odds ratios (95% CI) for depression

Model 1a Model 2b Model 3c Model 4d
Parental set bedtime on weekday nights
10:00 PM or earlier 1.00 1.00 1.00 1.00
By 11:00 PM 1.15 (0.94-1.40) 1.13 (0.90-1.42) 1.10 (0.87-1.39) 0.97 (0.76-1.24)
By or after midnight 1.42 (1.21-1.67) 1.28 (1.07-1.52) 1.24 (1.04-1.49) 1.07 (0.88-1.30)
Self-perception of how much parents care
1 – Not at all 6.82 (3.11-14.98) 5.88 (2.79-12.40)
2 – Very little 8.32 (4.58-15.12) 6.73 (3.49-12.98)
3 – Somewhat 5.50 (3.72-8.13) 4.93 (3.32-7.30)
4 – Quite a bit 2.43 (1.89-3.13) 2.16 (1.69-2.76)
5 – Very much 1.00 1.00
Adolescent-reported sleep duration
≤ 5 h 1.71 (1.22-2.39)
6 h 1.29 (0.97-1.70)
7 h 1.19 (0.96-1.48)
8 h 1.00
9 h 1.17 (0.88-1.56)
≥ 10 h 1.34 (0.95-1.89)
Enough Sleep 0.35 (0.28-0.43)
aModel 1 – Unadjusted.
bModel 2 – Adjusted for age, sex, race/ethnicity, parent’s marital status, and family receipt of public assistance.
cModel 3 – Adjusted for variables in Model 2 plus self perception of how much parents care.
dModel 4 – Adjusted for variables in Model 3 plus adolescent reported sleep duration and perception of getting enough sleep.

The results from this study provide new evidence to support the notion that short sleep duration could play a role in the etiology of depression. Earlier bedtimes could therefore be protective against adolescent depression and suicidal ideation by lengthening sleep duration.

Young athletes have to cope nowadays with various stresses, not only performance related. Studying, maintaining social contacts, training, family and peer pressure are all parts of young athlete’s  lives. Sleep is a simple thing that can make sure they recover properly and can cope with everything they have to deal with.

So, are we making sure they get good quality and good amounts of sleep?

Do we advice them on appropriate bed time?

Do we make sure they don’t spend the night playing videogames or chatting on social networks?

Do we create the right sleeping environment and routines?

Do we know if they are sleeping well?

How about a checklist?

Read Atul Gawande’s book about checklists, The Checklist Manifesto. Not only is the book loaded with fascinating stories, but it honestly changed the way I think about the world. The book’s main point is simple: no matter how expert you may be, well-designed check lists can improve outcomes. So, let’s make sure our young athletes tick all the boxes when it comes to sleep.

Ice and cold water after resistance exercise: are you sure it’s a good idea?

As I mentioned in a previous post on this blog I am developing an interest in recovery strategies. I am amazed of how many tools/devices/procedures/methods are nowadays used to provide a "recovery" solution to athletes.

What I am most amazed of is the total lack of rationale behind many recovery strategies, not to mention the lack of scientific evidence for their effectiveness.

It seems to me that many strength and conditioning coaches, physiotherapists, sports scientists sometimes accept some practices without really questioning why they should be using them. Unfortunately most of the times a particular recovery strategy is used just because a winning team or athlete made extensive and public use of it.

Let’s talk about Ice Baths and cold water immersion. The following picture shows what happens typically after some heavy training session these days:

Spa-ing partners: Bulldogs players take an ice bath during a recovery session at Canterbury pool. Photo: Craig Golding:Vailable at:http://www.smh.com.au/articles/2004/09/20/1095651251602.html

 

The reasons why athletes have to be exposed to this "torture" are the following as advocated by many S&C coaches and Physios:

  • Helps in reducing DOMS and inflammation
  • Helps in reducing swelling
  • Helps in improving blood flow
  • Helps in favouring recovery

In this article I will focus on the first point. There seems to be nowadays the need to make sure that Athletes have no DOMS (delayed onset of muscle soreness) after a training session and most of all there is a need to avoid inflammation.

With this approach, it seems that the focus of attention is now shifting away from what athletes normally do to improve performance: training!

What is training all about?

Athletes undergo gruelling training sessions to improve performance. They lift weights to get stronger, run/cycle/row to improve their endurance or speed. Simple!

The reason why they do it is to create an overload on their biological system to produce an adaptive response leading to a stronger muscle, a better cardio-respiratory system, stronger bones. They also do it to improve muscle biochemistry which then leads to better muscle function (i.e. buffering systems, metabolic enzymes).

In particular, when athletes lift heavy weights, they do it to determine muscle hypertrophy and to get stronger. The typical consequence of a weight lifting session is muscle damage then followed by an inflammatory phase and a regeneration phase able to determine a stronger muscle (for some interesting reading download this PDF of a review written by Prof. Priscilla Clarkson http://www.nmdinfo.net/Publications/Consensus%20Conf%202002%20Papers/Clarkson.pdf)

So, in simple terms, we want muscle damage, inflammation and swelling as their are the main signaling mechanisms triggering muscle remodelling (http://www.ncbi.nlm.nih.gov/pubmed/17887809?ordinalpos=7&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum).

Training-induced molecular and humoral adjustments, including muscle hyperthermia, are physiological, transient and essential for training effects (myofiber regeneration, muscle hypertrophy and improved blood supply). Stopping them may be not a good idea.

So, by reducing DOMS, swelling and inflammation are we stopping adaptations?

Maybe that’s the case. Recent studies have shown that applying cryotherapy to muscles after training reduces the training gains. Yamane et al. (2006) exposed two groups of volunteers to the same training programme and a different recovery strategy. One group was in fact asked to rest at room temperature, the other were asked to immerse the trained limbs in cold-water post training. The results showed that the group with a normal recovery improved more and the authors concluded that cooling generally attenuates the temperature-dependent processes generated by training, in particular, hyperthermia-induced HSP formation"

image

Is cryotherapy actually effective in reducing DOMS?

Science says that:Cryotherapy does not reduce DOMS symptoms (Cheung et al., Sports Med, 2003)

Cold water immersion had NO effect on perception of tenderness and strength loss (Eston & Peters, JSS, 1999)

The use of cryotherapy immediately following damaging eccentric exercise may not provide the same therapeutic benefits commonly attributed to cryotherapy following traumatic muscle injury (Paddon-Jones & Quigley ,1997 IJSM)

Recovery of muscle soreness, flexibility and power at 48 hr post-game was not significantly enhanced by performing an immediate post-game recovery beyond that achieved by performing only next day recovery training (Dawson et al., J Sci Med Sport, 2005)

Sellwood et al (2007) recently concluded that "The protocol of ice-water immersion used in their study was ineffectual in minimising markers of DOMS in untrained individuals (3 x 1min immersion in ice water). This study challenges the wide use of this intervention as a recovery strategy by athletes".

There are of course many others out there…

What can we conclude?

Using cryotherapy and cold water immersion with athletes is a very bad idea if you are training them to get stronger!

If you want to reduce pain and swelling and help with recovery in athletes performing at tournaments then you are better off with other strategies. But this is something to talk about in the next article!

MC