Monday, July 20, 2015

Does regular post-exercise cold application attenuate training adaptations?

That's a fundamental questions asked by many coaches and practitioners over the last year(s) ( This concern is growing as more data is published showing that regular cold application might attenuate training adaptations.

What's new?
Yamane and colleagues (2015) asked their participants to train with wrist flexion exercises, 3 times a week for 6 weeks. Seven subjects immersed their forearms in cold water (10 ± 1°C) for 20 min after each training whereas the other 7 didn't immerse their limbs. Their results showed that regular post-exercise cold application attenuated muscular and vascular adaptations to this type of training (

In a more recent study, 21 active males participated in a strength training program for 12 weeks. Post-exercise recovery included either 10-min cold water immersion (CWI) or active recovery. Their results showed that CWI attenuates the exercise training induced hypertrophy (

Points to consider
Although both studies provide novel data on the potential role of regular post-exercise cold water immersion on training adaptations, they are not without limitations. Their main limitation is that participants were non-trained and, thus, we don't know if these results apply to trained individuals.

Evidence against 
On the other side, Ihsan et al. (2015) recently showed that regular cold water immersion following endurance training sessions may enhance mitochondrial biogenesis ( As in the above mentioned studies, non-trained subjects were recruited and this limits the applications of these findings.

Take-home message
My opinion is that there is evidence that regular post-exercise cold application attenuates adaptations to training. We should acknowledge however that this information comes from non-trained males following strength training. Until more data in trained and possibly elite individuals are published we should be more concerned with the regular application of cold as a means of recovery.

Friday, July 10, 2015

Training load assessment in elite football players: should we trust what we read?

with Djibril Cisse  (Pre-season camp in Austria, July 2010)

As most of you know, training load (TL) assessment is vital to injury prevention strategy development. There are various tools of TL assessment, with the Rate of Perceived Exertion being one of the most popular. 

In one of our papers (Brito, Hertzog, Nassis 2015), accepted for publication last week, we analysed the TL of highly trained football players daily throughout the entire season. The fatigue index was assessed once per week for the same period. 

Our main finding was that training load was affected by a number of factors like previous and next match result and location. In addition, although TL fluctuated throughout the year the fatigue index remains relatively stable. Given the limitations of our methodology, we speculate that highly-trained players choose their pace during training in order to avoid excess fatigue throughout the season.

Practical implications

1) RPE-based training load assessment might not be as accurate as we think, and 
2) highly-trained players have the ability to modify their pace in order to avoid excessive fatigue. Although this speculation remains to be proved with more robust experimental designs, our data suggest we should consider modifying our strategies on fatigue & injury prevention.

The abstract of this study can be reached at 

Friday, June 12, 2015

Post-exercise recovery: time to reconsider our practice?

Following the last week's post (here, I have received a number of emails with valid comments. Thank you all for that!

It is evident that post-exercises strategy is a "hot" topic in sports. There is substantial literature on that topic. Does this knowledge makes a big difference in the field? 

Based on my experience, there is need for more work on the applicability of the post-recovery strategies in a real life set-up. For instance, players' compliance to some recovery methods is variable, if not low, at some periods. This is of course a fact that affects the methods' effectiveness.

In a previous post, I highlight the findings of a study that examined player's perception on recovery methods and the effectiveness of these methods on recovery (here

To summarize my thoughts, I believe that:
  • we need to implement a more holistic approach by applying various methods depending on the athlete's belief and the period of the year
  • we must improve players buy-in. If athletes believe on the method, they will comply and this might result in better recovery.

Again, your contribution is very much appreciated.


Friday, June 5, 2015

Cold water immersion for recovery: is it all in our mind?

Cold water immersion is a very popular strategy for recovery after exercise. Although there is evidence on its benefits on perception of fatigue no consensus exists on its effect on performance. In addition, many studies show no effect of this strategy on physiological functions. Part of the confusion might be due to the studies' design. Indeed, most studies have not used a placebo condition and this could have affected the conclusion and hence the practical applications.

The study of Broatch et al (2014) investigated if the placebo effect is responsible for any acute performance and psychological benefit of postexercise cold water immersion. Following a high-intensity interval session, the participants followed one of the 3 following recovery conditions i) cold water immersion at 10 oC, ii) thermoneutral water immersion placebo (34.7 oC), iii) thermoneutral water immersion control (34.7 oC). 

Their conclusion was that a recovery placebo administered after high-intensity exercise was as effective as cold water immersion in the recovery of muscle strength over 48 hours. In addition, both the cold water and the thermoneutral immersion placebo resulted in faster recovery of strength compared with the control condition.

This study shows that at least part of any benefit of cold water immersion is due to a placebo effect.

How this study might affect practice?

  • Postexercise water immersion even at around 30 oC may produce similar performance improvements compared to cold water immersion provided we lead athletes believe that thermoneutral water immersion is beneficial on performance recovery.
  • Medical & sports science staff should not be so concerned about the water temperature itself. 
  • Thermoneutral water immersion is more comfortable to athletes and this should be taken into consideration when planning a recovery strategy.

Some concerns

  • This study examined the recovery of muscle strength. We don't know what might happen with the application of the same recovery strategy on other performance parameters such as speed, repeated sprints ability and endurance.

Broatch et al (2014). Med Sci Sports Exerc, 46(11):2139-47.

Friday, May 15, 2015

Training or competing in the heat: how to protect your health & boost performance?
In the below article you can find the most recent update on recommendations for event organizers, athletes, coaches and scientists. You can download free from the Scandinavian Journal of Medicine & Science in Sports at

Friday, April 24, 2015

Altitude & performance: what's new?

 2015 Feb 9. [Epub ahead of print]

"Live High-Train Low and High" Hypoxic Training Improves Team-Sport Performance.



To investigate physical performance and hematological changes in 32 elite male team-sport players after 14 days of 'live high-train low' (LHTL) in normobaric hypoxia (≥14 at 2800-3000 m) combined with repeated-sprint training (6 sessions of 4 sets of 5 x 5-s sprints with 25 s of passive recovery) either in normobaric hypoxia at 3000 m (LHTL+RSH, namely LHTLH; n = 11) or in normoxia (LHTL+RSN, namely LHTL; n = 12) compared to controlled 'live low-train low' (LLTL; n = 9).


Prior to (Pre-), immediately (Post-1) and 3 weeks (Post-2) after the intervention, hemoglobin mass (Hbmass) was measured in duplicate (optimized carbon monoxide rebreathing method) and vertical jump, repeated-sprint (8 x 20 m - 20 s recovery) and Yo-Yo Intermittent Recovery level 2 (YYIR2) performances were tested.


Both hypoxic groups increased similarly Hbmass at Post-1 and Post-2 in reference to Pre- (LHTLH: +4.0%, P<0.001 and +2.7%, P<0.01; LHTL: +3.0% and +3.0%, both P<0.001), while no change occurred in LLTL. Compared to Pre-, YYIR2 performance increased by ∼21% at Post-1 (P<0.01) and by ∼45% at Post-2 (P<0.001) with no difference between the two intervention groups (vs. no change in LLTL). From Pre- to Post-1 cumulated sprint time decreased in LHTLH (-3.6%, P<0.001) and in LHTL (-1.9%, P<0.01), but not in LLTL (-0.7%), and remained significantly reduced at Post-2 (-3.5% P<0.001) in LHTLH only. Vertical jump performance did not change.


'Live high-train low and high' hypoxic training interspersed with repeated sprints in hypoxia for 14 days (in-season) increases Hbmass, YYIR2 performance and repeated-sprint ability of elite field team-sport players with the benefits lasting for at least three weeks post-intervention.

 2015 Jan 26. [Epub ahead of print]

Altitude Training in Elite Swimmers for Sea Level Performance (Altitude Project).


This controlled nonrandomized parallel groups trial investigated the effects on performance, V˙o2 and hemoglobin mass (tHbmass) of 4 preparatory in-season training interventions: living and training at moderate altitude for 3 and 4 weeks (Hi-Hi3, Hi-Hi), living high and training high and low (Hi-HiLo, 4 weeks), and living and training at sea level (SL) (Lo-Lo, 4 weeks).


From 61 elite swimmers, 54 met all inclusion criteria and completed time trials over 50 and 400 m crawl (TT50, TT400), and 100 (sprinters) or 200 m (non-sprinters) at best stroke (TT100/TT200). V˙o2max and heart rate were measured with an incremental 4x200-m test. Training load was estimated using TRIMPc and session RPE. Initial measures (PRE) were repeated immediately (POST) and once weekly on return to SL (PostW1 to PostW4). tHbmass was measured in duplicate at PRE and once weekly during the camp with CO rebreathing. Effects were analyzed using mixed linear modeling.


TT100 or TT200 was worse or unchanged immediately POST, but improved by ∼3.5% regardless of living or training at SL or altitude following at least 1 week of sea level recovery. Hi-HiLo achieved a greater improvement two (5.3%) and four weeks (6.3%) after the camp. Hi-HiLo also improved more in TT400 and TT50 two (4.2% and 5.2%, respectively) and four weeks (4.7% and 5.5%) from return. This performance improvement was not linked linearly to changes in V˙o2max or tHbmass.


A well- implemented 3- or 4-week training camp may impair performance immediately, but clearly improves performance even in elite swimmers after a period of SL recovery. Hi-HiLo for 4 weeks improves performance in swimming above and beyond altitude and SL controls, through complex mechanisms involving altitude living and SL training effects.

 2015 Feb 24. [Epub ahead of print]

Effects of Altitude on Performance of Elite Track-and-Field Athletes.



Lower barometric pressure of air at altitude can affect competitive performance of athletes in some sports. Here we report the effects of various altitudes on elite track-and-field athlete's performance.


Lifetime track-and-field performances of athletes placed in the top 16 in at least one major international competition between 2000 and 2009 were downloaded from the database at There were 132,104 performances of 1889 athletes at 794 venues. Performances were log-transformed and analyzed using a mixed linear model with fixed effects for 6 levels of altitude and random quadratic effects to adjust for athlete's age.


Men's and women's sprint events (100-400 m) showed marginal improvements of ~0.2% at altitudes of 500-999 m, and above 1500 m all but the 100-and 110-m hurdles showed substantial improvements of 0.3-0.7%. Some middle- and long-distance events (800-10,000 m) showed marginal impairments at altitudes above 150 m, but above 1000 m the impairments increased dramatically to ~2-4% for events >800 m. There was no consistent trend in the effects of altitude on field events up to 1000 m; above 1000 m hammer throw showed a marginal improvement of ~1%, and discus was impaired by 1-2%. Above 1500 m, triple jump and long jump showed marginal improvements of ~1%.


In middle-and long-distance runners altitudes as low as 150-299 m can impair performance. Higher altitudes (≥ 1000 m) are generally required before decreases in discus performance, or enhancements in sprinting, triple-and long-jump, or hammer throw are seen.

Saturday, April 18, 2015

Performance during the 2014 FIFA World Cup: download free from BJSM

The association of environmental heat stress with performance: analysis of the 2014 FIFA World Cup Brazil

  • George P Nassis
  • Joao Brito
  • Jiri Dvorak
  • Hakim Chalabi
  • Sebastien Racinais
Br J Sports Med 2015;49:609-613 Published Online First: 17 February 2015

Tuesday, February 24, 2015

Does heat affect football performance?

To contribute into this discussion we have analyzed performance data during the 2014 FIFA World Cup BrazilTM in relation to environmental heat stress. A summary of the findings is presented in this table. 

Soon, the full paper will have open access.

Saturday, January 31, 2015

Think different, innovative & act effectively

Here I am again after a period of silence. This was intentional to re-think the approach. As you can see, I decided to “re-brand” the blog to make it more useful (I hope!). Why this change?

Think different: I believe to make a step forward we need to look at things from a different angle. Not necessarily good but, for sure, we learn a lot.

Think innovative: I know this is a “big” word. Nowadays, many experts talk about innovation. I am not an expert but I think if we learn to look from a different angle or read below the lines we might find some good stuff.

Act effectively: To my experience, this is what is missing in sports & exercise science; the link between science and practice. The trend these years is to move towards “translation research” meaning research that will seek to answer practical questions & which will make the difference on the field. Again, this is not the end of the story. A key step in achieving this translation is the effective communication between the scientists and the practitioners.

Everyone has examples of ineffective plans. As an example, if training load is a key parameter in injury prevention in elite football, why many elite clubs don’t use this tool effectively? If science and medicine have made advancements in injury prevention why the rate of non-contact injuries remains high?

In the public health domain, why the vast majority of people do not take regular physical activity? This is despite the huge number of studies showing that regular physical activity protects from premature death.

Do we miss something?

I am happy to post your thought & ideas under the condition you identify yourself.

Hope you enjoy the posts from today. 



PS: The next 2 posts will be on the two examples I brought to your attention above. Stay tuned!

Friday, September 19, 2014

How to boost performance on the competition day?

Coaches and sport scientists mainly focus on how to train better the days before and recover fasted in the hours/days after training and matches. No doubt that training quality is the foundation of peak performance. Another window of opportunity is the day and hours before competition. What can we do to maximize potential? This is a summary of strategies based on recent evidence:

In the competition day
Warm up: The aim is to elevate muscle and body's temperature at an optimal level. An increase in warm up intensity in the cold days and a reduction in the post-warm up recovery has been shown to improve performance. When time between warm-up and actual start of competition is long, use strategies like passive heat to maintain muscle and body temperature. 

Postactivation potentiation: It can be induced with exercise intensities ranging from 75-95% of 1RM. The optimal recovery period is 8-12min. Research also suggest the use of plyometrics.

Hormonal optimization: This can be achieved by various means such as:
-High-intensity training 3-7 hours before competition
-strength training 3-7 hours before competition (see postactivation potentiation above)
-ischemic training via partial working muscles blood flow restriction.

It must be noted that evidence is very limited so far. Also the existing research is mainly in healthy individuals and not in competitive and, more importantly, high level athletes.

For further reading
Kilduff et al (2013). Int J Sports Physiol Perform

Monday, July 14, 2014

How to use easy to conduct tests for players monitoring: an example

Germany vs Argentina (13/7/2014)
Acute responses of soccer match play on hip strength and flexibility measures: potential measure of injury risk

Darren J. Paul, George P. Nassis, Rodney Whiteley, Joao B. Marques, Dean Kenneally & Hakim Chalabi Journal of Sports Sciences, 2014 Vol. 32, No. 13, 1318–1323, FREE to download from Journal of Sports Sciences (14/7/2014)

Saturday, July 12, 2014

Recent studies on football (FREE to download)
Below you can find some recent papers with practical applications to football (soccer). They are free to download form the journals official sites.

How Small-Sided and Conditioned Games Enhance Acquisition of Movement and Decision-Making Skills. Exercise & Sport Sciences Reviews: July 2013 - Volume 41 - Issue 3 - p 154–161


The Influence of Soccer Playing Actions on the Recovery Kinetics After a Soccer Match. 
Journal of Strength & Conditioning Research June 2014 - Volume 28 - Issue 6 - p 1517–1523

Soccer Training Improves Cardiac Function in Men with Type 2 Diabetes.
Medicine & Science in Sports & Exercise December 2013 - Volume 45 - Issue 12 - p 2223–2233

Friday, June 20, 2014

How to find the top performers?

We are all wondering how to identify a talent. Meetings, research projects, tests, papers and hard work. We are all doing our best. Here, I post a presentation from Rasmus Ankersen the author of "The Gold Mine effect". Rasmus is not a scientist but he can add a "fresh" look to the problem as an outsider.
I hope you all find this video useful.

Monday, June 2, 2014

Effect of cold water immersion on long term adaptations: time to re-consider the practice?

There was a number of interesting abstracts during the ACSM last week in Orlando, Florida. Today, I would like to comment on the study presented by Roberts and colleagues from Australia which received one of the international student awards.

You might remember that in one of my posts in this blog about 3 years ago, I raised the issue of possible negative impact of frequent cold water immersion (CWI) on long term adaptations to training. For your information this is the post

This speculation, at that time, was based on the fact that CWI seems to suppress inflammation which is part of the exercise training-induced adaptation process.

The group from Australia tested this idea in 21 men split in two groups. One group performed high-intensity resistance training twice a week for 12 weeks plus lower body CWI for 10min post exercise. The other group performed the same training but instead of CWI they cycled at low intensity for 10min post-training. Training adaptations were assessed by measuring changes in maximal isometric torque and rate of force development (RFD), isokinetic dynamic strength, leg press and knee extension strength.

Their results showed that training-induced changes in isometric torque and isokinetic torque, RFD and knee extension strength were signifi cantly smaller in the CWI group.

Based on these findings, it seems that regular CWI may attenuate the exercise training-induced performance improvements.

Roberts et al. MSSE 46(5): S192

Sunday, April 20, 2014

Recent studies with applications to real life sporting settings

Vitamin C and E supplementation hampers cellular adaptation to endurance training in humans

FREE to download from the Journal of Physiology

Paulsen et al. J Physiol 2014;592:1887-1901

In this double-blind, randomised, controlled trial, we investigated the effects of vitamin C and E supplementation on endurance training adaptations in humans. Fifty-four young men and women were randomly allocated to receive either 1000 mg of vitamin C and 235 mg of vitamin E or a placebo daily for 11 weeks. During supplementation, the participants completed an endurance training programme consisting of three to four sessions per week (primarily of running), divided into high-intensity interval sessions [4-6 × 4-6 min; >90% of maximal heart rate (HRmax)] and steady state continuous sessions (30-60 min; 70-90% of HRmax). Maximal oxygen uptake (VO2 max ), submaximal running and a 20 m shuttle run test were assessed and blood samples and muscle biopsies were collected, before and after the intervention. Participants in the vitamin C and E group increased their VO2 max (mean ± s.d.: 8 ± 5%) and performance in the 20 m shuttle test (10 ± 11%) to the same degree as those in the placebo group (mean ± s.d.: 8 ± 5% and 14 ± 17%, respectively). However, the mitochondrial marker cytochrome c oxidase subunit IV (COX4) and cytosolic peroxisome proliferator-activated receptor-γ coactivator 1 α (PGC-1α) increased in the m. vastus lateralis in the placebo group by 59 ± 97% and 19 ± 51%, respectively, but not in the vitamin C and E group (COX4: -13 ± 54%; PGC-1α: -13 ± 29%; P ≤ 0.03, between groups). Furthermore, mRNA levels of CDC42 and mitogen-activated protein kinase 1 (MAPK1) in the trained muscle were lower in the vitamin C and E group than in the placebo group (P ≤ 0.05). Daily vitamin C and E supplementation attenuated increases in markers of mitochondrial biogenesis following endurance training. However, no clear interactions were detected for improvements in VO2 max and running performance. Consequently, vitamin C and E supplementation hampered cellular adaptations in the exercised muscles, and although this did not translate to the performance tests applied in this study, we advocate caution when considering antioxidant supplementation combined with endurance exercise.

Burns KJ, Pollock BS, Lascola P, McDaniel J. Cardiovascular responses to counterweighted single-leg cycling: implications for rehabilitation. Eur J Appl Physiol. 2014 May;114(5):961-8. 

PURPOSE: Although difficult to coordinate, single-leg cycling allows for greater muscle-specific exercise capacity and subsequently greater stimulus for metabolic and vascular adaptations compared to typical double-leg cycling. The purpose of this investigation was to compare metabolic, cardiovascular and perceptual responses of double-leg cycling to single-leg cycling with and without the use of a counterweight. METHODS: Ten healthy individuals (age 22 ± 2 years; body mass 78.0 ± 11.2 kg; height 1.8 ± 0.1 m) performed three cycling conditions consisting of double-leg cycling (DL), non-counterweighted single-leg cycling (SLNCW) and single-leg cycling with a 97 N counterweight attached to the unoccupied crank arm (SLCW). For each condition, participants performed cycling trials (80 rpm) at three different work rates (40, 80 and 120 W). Oxygen consumption (VO2), respiratory exchange ratio (RER), heart rate (HR), femoral blood flow, rating of perceived exertion (RPE) and liking score were measured. RESULTS: VO2 and HR were similar for DL and SLCW conditions. However, during SLNCW, VO2 was at least 23 ± 13 % greater and HR was at least 15 ± 11 % greater compared to SLCW across all three intensities. Femoral blood flow was at least 65.5 ± 43.8 % greater during SLCW compared to DL cycling across all three intensities. RPE was lower and liking scores were greater for SLCW compared to SLNCW condition. CONCLUSION: Counterweighted single-leg cycling provides an exercise modality that is more tolerable than typical single-leg cycling while inducing greater peripheral stress for the same cardiovascular demand as double-leg cycling.

Nilstad A, Bahr R, Andersen TE. Text messaging as a new method for injury registration in sports: a methodological study in elite female football. Scand J Med Sci Sports. 2014 Feb;24(1):243-9.

Methodological differences in epidemiologic studies have led to significant discrepancies in injury incidences reported. The aim of this study was to evaluate text messaging as a new method for injury registration in elite female football players and to compare this method with routine medical staff registration. Twelve teams comprising 228 players prospectively recorded injuries and exposure through one competitive football season. Players reported individually by answering three text messages once a week. A designated member of the medical staff conducted concurrent registrations of injuries and exposure. Injuries and exposure were compared between medical staff registrations from nine teams and their 159 affiliated players. During the football season, a total of 232 time-loss injuries were recorded. Of these, 62% were captured through individual registration only, 10% by the medical staff only, and 28% were reported through both methods. The incidence of training injuries was 3.7 per 1000 player hours when calculated from individual registration vs 2.2 from medical staff registration [rate ratio (RR): 1.7, 1.2-2.4]. For match injuries, the corresponding incidences were 18.6 vs 5.4 (RR: 3.4, 2.4-4.9), respectively. There was moderate agreement for severity classifications in injury cases reported by both methods (kappa correlation coefficient: 0.48, confidence interval: 0.30-0.66).

Areta JL, Burke LM, Camera DM et al. Reduced resting skeletal muscle protein synthesis is rescued by resistance exercise and protein ingestion following short-term energy deficit. Am J Physiol Endocrinol Metab 2014;306:E989-997

The myofibrillar protein synthesis (MPS) response to resistance exercise (REX) and protein ingestion during energy deficit (ED) is unknown. In young men (n = 8) and women (n = 7), we determined protein signaling and resting postabsorptive MPS during energy balance [EB; 45 kcal·kg fat-free mass (FFM)(-1)·day(-1)] and after 5 days of ED (30 kcal·kg FFM(-1)·day(-1)) as well as MPS while in ED after acute REX in the fasted state and with the ingestion of whey protein (15 and 30 g). Postabsorptive rates of MPS were 27% lower in ED than EB (P < 0.001), but REX stimulated MPS to rates equal to EB. Ingestion of 15 and 30 g of protein after REX in ED increased MPS ∼16 and ∼34% above resting EB (P < 0.02). p70 S6K Thr(389) phosphorylation increased above EB only with combined exercise and protein intake (∼2-7 fold, P < 0.05). In conclusion, short-term ED reduces postabsorptive MPS; however, a bout of REX in ED restores MPS to values observed at rest in EB. The ingestion of protein after REX further increases MPS above resting EB in a dose-dependent manner. We conclude that combining REX with increased protein availability after exercise enhances rates of skeletal muscle protein synthesis during short-term ED and could in the long term preserve muscle mass.

Saturday, April 19, 2014

Who is leading the change in a Club or Organization?

Look at the best clubs and the best teams in the world, being in sport or other sector. What do they have in common?

Someone might say that it is the players/employees who make the difference in a team or organization. I would agree, at least in part. No change will happen if the CEO or the Board of Directors or the Head Manager, whoever is leading the team/organization, are not ready for the change and are not convinced about the “where to go”.

The leader will develop the vision & the strategic plan, he will communicate it with all people involved and will inspire them to work hard every day for the common purpose.

If (the leader) has a clear vision he will place the right people at the right position. This will be one of the first steps for a successful journey.

Take home message
Next time choose your manager!

For further reading
Jim Collins. Good to Great. Harper Business, 2001

Anita Elberse with Sir Alex Ferguson. Ferguson's formula. Harvard Business Reviews, October 2013  

Friday, March 28, 2014

Effect of cryotherapy on performance: what's new?

Open Access J Sports Med. 2014 Mar 10;5:25-36. eCollection 2014.

Whole-body cryotherapy: empirical evidence and theoretical perspectives. Bleakley CM, Bieuzen F, Davison GW, Costello JT.

Whole-body cryotherapy (WBC) involves short exposures to air temperatures below -100°C. WBC is increasingly accessible to athletes, and is purported to enhance recovery after exercise and facilitate rehabilitation postinjury. Our objective was to review the efficacy and effectiveness of WBC using empirical evidence from controlled trials. We found ten relevant reports; the majority were based on small numbers of active athletes aged less than 35 years. Although WBC produces a large temperature gradient for tissue cooling, the relatively poor thermal conductivity of air prevents significant subcutaneous and core body cooling. There is weak evidence from controlled studies that WBC enhances antioxidant capacity and parasympathetic reactivation, and alters inflammatory pathways relevant to sports recovery. A series of small randomized studies found WBC offers improvements in subjective recovery and muscle soreness following metabolic or mechanical overload, but little benefit towards functional recovery. There is evidence from one study only that WBC may assist rehabilitation for adhesive capsulitis of the shoulder. There were no adverse events associated with WBC; however, studies did not seem to undertake active surveillance of predefined adverse events. Until further research is available, athletes should remain cognizant that less expensive modes of cryotherapy, such as local ice-pack application or cold-water immersion, offer comparable physiological and clinical effects to WBC.

FULL paper

Int J Sports Physiol Perform. 2013 May;8(3):227-42. Epub 2013 Feb 20.
Cooling and performance recovery of trained athletes: a meta-analytical review. Poppendieck W, Faude O, Wegmann M, Meyer T.

PURPOSE: Cooling after exercise has been investigated as a method to improve recovery during intensive training or competition periods. As many studies have included untrained subjects, the transfer of those results to trained athletes is questionable. METHODS: Therefore, the authors conducted a literature search and located 21 peer-reviewed randomized controlled trials addressing the effects of cooling on performance recovery in trained athletes. RESULTS: For all studies, the effect of cooling on performance was determined and effect sizes (Hedges' g) were calculated. Regarding performance measurement, the largest average effect size was found for sprint performance (2.6%, g = 0.69), while for endurance parameters (2.6%, g = 0.19), jump (3.0%, g = 0.15), and strength (1.8%, g = 0.10), effect sizes were smaller. The effects were most pronounced when performance was evaluated 96 h after exercise (4.3%, g = 1.03). Regarding the exercise used to induce fatigue, effects after endurance training (2.4%, g = 0.35) were larger than after strength-based exercise (2.4%, g = 0.11). Cold-water immersion (2.9%, g = 0.34) and cryogenic chambers (3.8%, g = 0.25) seem to be more beneficial with respect to performance than cooling packs (-1.4%, g= -0.07). For cold-water application, whole-body immersion (5.1%, g = 0.62) was significantly more effective than immersing only the legs or arms (1.1%, g = 0.10). CONCLUSIONS: In summary, the average effects of cooling on recovery of trained athletes were rather small (2.4%, g = 0.28). However, under appropriate conditions (whole-body cooling, recovery from sprint exercise), postexercise cooling seems to have positive effects that are large enough to be relevant for competitive athletes.

J Strength Cond Res. 2014 Mar 11. [Epub ahead of print]
Effect of run training and cold-water immersion on subsequent cycle training quality in high performance triathletes. Rowsell GJ, Reaburn P, Toone R, Smith M, Coutts AJ.

The purpose of the study was to investigate the effect of cold-water immersion (CWI) on physiological, psychological, and biochemical markers of recovery and subsequent cycling performance following intensive run training. Seven high-performance male triathletes (age: 28.6±7.1 y; cycling VO2peak: 73.4±10.2 mL·kg·min) completed two trials in a randomized crossover design consisting of 7 x 5-min running intervals at 105% of Individual Anaerobic Threshold followed by either CWI (10°C±0.5°C) or thermoneutral water immersion (TNI; 34±0.5°C). Subjects immersed their legs in water five times for 60-s with 60-s passive rest between each immersion. Nine hours post-immersion, inflammatory and muscle damage markers, and perceived recovery measures were obtained before the subjects completed a 5-min maximal cycling test followed by a high quality cycling interval training set (6 x 5-min intervals). Power output, heart rate (HR), blood lactate (La) and rating of perceived exertion (RPE) were also recorded during the cycling time-trial and interval set. Performance was enhanced (change, ±90% confidence limits) in the CWI condition during the cycling interval training set (power output (W·kg ), 2.1±1.7%, La (mmol·L), 18±18.1%, La:RPE, 19.8±17.5%). However, there was an unclear effect of CWI on 5-min maximal cycling time-trial performance and there was no significant influence on perceptual measures of fatigue/recovery, despite small to moderate effects. The effect of CWI on the biochemical markers was mostly unclear, however there was a substantial effect for interleukin-10 (20±13.4%). These results suggest that compared to TNI, CWI may be effective for enhancing cycling interval training performance following intensive interval running training.

J Sport Rehabil. 2014 Mar 12. [Epub ahead of print]
Comparison of Electrical Stimulation Versus Cold Water Immersion Treatment on Muscle Soreness Following Resistance Exercise. Jajtner AR, Hoffman JR, Gonzalez AM, Worts P, Fragala MS, Stout JR.

CONTEXT: Resistance training is a common form of exercise for competitive and recreational athletes. Enhancing recovery from resistance training may potentially improve the muscle remodeling processes, stimulating a faster return to peak performance. OBJECTIVE: To examine the effects of two different recovery modalities, neuromuscular electrical stimulation (NMES), and cold water immersion (CWI) on performance, biochemical and ultrasonographic measures. PARTICIPANTS: Thirty resistance-trained males (23.1±2.9yrs; 175.2±7.1cm; 82.1±8.4kg) were randomly assigned to NMES, CWI or control (CON). DESIGN AND SETTING: All participants completed a high-volume lower-body resistance training workout on day one and returned to the Human Performance Lab 24- (24H) and 48h (48H) post-exercise for follow-up testing. MEASURES: Blood samples were obtained pre-exercise (PRE), immediately post (IP), 30-minutes post (30P), 24H and 48H. Subjects were examined for performance changes in the squat exercise (total repetitions, and average power per repetition), biomarkers of inflammation, and changes in cross sectional area (CSA) and echo intensity (EI) of the rectus femoris (RF) and vastus lateralis (VL) muscles. RESULTS: No differences between groups were observed in the number of repetitions (p=0.250; power: p=0.663). Inferential based analysis indicated that increases in C-reactive protein (CRP), concentrations were likely increased by a greater magnitude following CWI compared to CON, while NMES possibly decreased more than CON from IP to 24H. Increases in IL-10 concentrations between IP-30P were likely greater in CWI than NMES, but not different compared to CON. Inferential based analysis of RF EI indicated a likely decrease for CWI between IP-48H. No other differences between groups were noted in any other muscle architecture measures. CONCLUSIONS: Results indicated that CWI induced greater increases in pro- and anti-inflammatory markers, while decreasing RF EI, suggesting CWI may be effective in enhancing short-term muscle recovery following high-volume bouts of resistance exercise.

Friday, March 14, 2014

Carbohydrate ingestion during exercise: time to rethink its role?

The effect of carbohydrate (CHO) ingestion on performance during prolonged exercise has been investigated in a number of studies. The majority of published papers show a positive effect. Does this fact mean that CHO ingestion during exercise is beneficial to exercise performance under all conditions? Is this effect due to biological advantage? 

Nassif and colleagues from the School of Human Movement Studies, Charles Sturt University, Australia, published a nice study in 2008 that questions the value of CHO ingestion during exercise.

What they did?
Nine well trained athletes with VO2max 65.8 ml/kg/min cycled at 70% of VO2max until volitional fatigue under three experimental conditions while
  • ingesting placebo capsules with distillated water (PLAc),
  • ingesting CHO capsules with distillated water (CHOc),
  • ingesting CHO capsules with distillated water whilst both researchers and athletes knew that CHO were being consumed (CHOk).

What they found?
  • Exercise duration was similar between PLAc and CHOc
  • Exercise duration was 24% longer in CHOk compared with PLAc

Take-home message
  • The ingestion of carbohydrate capsules did not improve performance under these experimental conditions.
  • Knowledge of the ingested ergogenic substance may improve performance. "Coaches and trainers of endurance athletes should be aware that knowledge of the performance enhancement supplement may have a significant psychological effect on endurance performance" (Nassif et al., 2008). 

Nassif et al. Double blind carbohydrate ingestion does not improve exercise duration in warm humid conditions. Journal of Science and Medicine in Sport 2008; 11: 72-79.