Snippit Sports Science

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Since 2008, Dr. Adam Storey has coached and managed various New Zealand weightlifting teams at key pinnacle events including the 2012 and 2016 Olympic Games and the 2010 and 2014 Commonwealth Games. During this time, Adam has coached weightlifters to Commonwealth Games medals and his athletes have broken over 250 New Zealand records in competition.

 

Adam’s specialist background in the area of strength and power conditioning lead to his role with High Performance Sport New Zealand as the Lead Strength and Conditioning Specialist for Athletics New Zealand. In this position he worked directly with 3 x Olympic Games medallist Valerie Adams.

 

Adam has a keen passion for rugby and he is currently employed by the Blues Super Rugby franchise as the Sports Science Manager and Assistant Trainer.

 

In addition to his role with the Blues, Adam is a Research Fellow within AUT’s SPRINZ department where he supervises post-graduate research in the areas of strength and conditioning and exercise physiology.

 

Adam's AUT Profile: https://www.aut.ac.nz/profiles/sport-recreation/research-fellow/adam-storey-profile

 

Adam's LinkedIn Profile: https://www.linkedin.com/in/adam-storey-phd-0709a78a

 

  

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Now that we are a few episodes in, we’ve had some great interactions with listeners. Some of the feedback received was that although the information in the papers that we spoke about was fantastic, the underlying mechanisms and information behind these papers would be beneficial.  One of the areas that we've had a great response to is Blood Flow Restriction training.  Hence, our first Snippit is on the use of localised (BFR) versus systemic (hypoxic chamber) hypoxia for resistance training. We enjoy your interactions and comments so please keep them coming. 

 

Sports Med. 2014 Aug; 44(8):1037-54

https://link.springer.com/article/10.1007%2Fs40279-014-0177-7

 

Hypoxia and resistance exercise: a comparison of localized and systemic methods.

Scott BR, Slattery KM, Sculley DV, Dascombe BJ

 

Abstract

 

It is generally believed that optimal hypertrophic and strength gains are induced through moderate- or high-intensity resistance training, equivalent to at least 60% of an individual's 1-repetition maximum (1RM). However, recent evidence suggests that similar adaptations are facilitated when low-intensity resistance exercise (~20-50% 1RM) is combined with blood flow restriction (BFR) to the working muscles.

 

Although the mechanisms underpinning these responses are not yet firmly established, it appears that localized hypoxia created by BFR may provide an anabolic stimulus by enhancing the metabolic and endocrine response, and increase cellular swelling and signalling function following resistance exercise.

 

Moreover, BFR has also been demonstrated to increase type II muscle fibre recruitment during exercise. However, inappropriate implementation of BFR can result in detrimental effects, including petechial haemorrhage and dizziness. Furthermore, as BFR is limited to the limbs, the muscles of the trunk are unable to be trained under localized hypoxia.

 

More recently, the use of systemic hypoxia via hypoxic chambers and devices has been investigated as a novel way to stimulate similar physiological responses to resistance training as BFR techniques. While little evidence is available, reports indicate that beneficial adaptations, similar to those induced by BFR, are possible using these methods. The use of systemic hypoxia allows large groups to train concurrently within a hypoxic chamber using multi-joint exercises.

 

However, further scientific research is required to fully understand the mechanisms that cause augmented muscular changes during resistance exercise with a localized or systemic hypoxic stimulus.

 

PMID: 24715613

DOI: 10.1007/s40279-014-0177-7

 

 

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Medicine & Science in Sports & Exercise

Issue: Volume 51(2), February 2019, p 288-298

Copyright: (C) 2019 American College of Sports Medicine

Publication Type: [APPLIED SCIENCES]

https://insights.ovid.com/crossref?an=00005768-201902000-00009

ISSN: 0195-9131

Accession: 00005768-201902000-00009

Keywords: ISCHEMIC TRAINING; KAATSU; MYOGENIC STEM CELLS, MYONUCLEAR ADDITION, MYONUCLEAR DOMAIN, ATHLETES

Type 1 Muscle Fiber Hypertrophy after Blood Flow-restricted Training in Powerlifters

BJORNSEN, THOMAS; WERNBOM, MATHIAS; KIRKETEIG, ALEXANDER; PAULSEN, GORAN; SAMNOY, LARS; BAEKKEN, LASSE5; CAMERON-SMITH, DAVID; BERNTSEN, SVEINUNG; RAASTAD, TRULS

ABSTRACT

Purpose:

To investigate the effects of blood flow-restricted resistance exercise (BFRRE) on myofiber areas (MFA), number of myonuclei and satellite cells (SC), muscle size and strength in powerlifters.

Methods:

Seventeen national level powerlifters (25 +/- 6 yr [mean +/- SD], 15 men) were randomly assigned to either a BFRRE group (n = 9) performing two blocks (weeks 1 and 3) of five BFRRE front squat sessions within a 6.5-wk training period, or a conventional training group (Con; n = 8) performing front squats at 60%-85% of one-repetition maximum (1RM). The BFRRE consisted of four sets (first and last set to voluntary failure) at ~30% of 1RM. Muscle biopsies were obtained from m. vastus lateralis (VL) and analyzed for MFA, myonuclei, SC and capillaries. Cross-sectional areas (CSA) of VL and m. rectus femoris were measured by ultrasonography. Strength was evaluated by maximal voluntary isokinetic torque (MVIT) in knee extension and 1RM in front squat.

Results:

BFRRE induced selective increases in type I MFA (BFRRE: 12% vs Con: 0%, P < 0.01) and myonuclear number (BFRRE: 18% vs Con: 0%, P = 0.02). Type II MFA was unaltered in both groups. BFRRE induced greater changes in VL CSA (7.7% vs 0.5%, P = 0.04), which correlated with the increases in MFA of type I fibers (r = 0.81, P = 0.02). No group differences were observed in SC and strength changes, although MVIT increased with BFRRE (P = 0.04), whereas 1RM increased in Con (P = 0.02).

Conclusions:

Two blocks of low-load BFRRE in the front squat exercise resulted in increased quadriceps CSA associated with preferential hypertrophy and myonuclear addition in type 1 fibers of national level powerlifters.

Snippit is sponsored by EliteForm, which brings together cutting edge sports science technologies.  Thank you EliteForm for making Snippit possible. Please visit https://eliteform.com and check out their products, StrengthPlanner and PowerTracker.

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Now that we are a few episodes in, we’ve had some great interactions with listeners. Some of the feedback received was that although the information in the papers that we spoke about was fantastic, the underlying mechanisms and information behind these papers would be beneficial.  One of the areas that we've had a great response to is Blood Flow Restriction training.  Hence, our first Snippit is on the use of localised (BFR) versus systemic (hypoxic chamber) hypoxia for resistance training. We enjoy your interactions and comments so please keep them coming. 

 

Sports Med. 2014 Aug; 44(8):1037-54

https://link.springer.com/article/10.1007%2Fs40279-014-0177-7

 

Hypoxia and resistance exercise: a comparison of localized and systemic methods.

Scott BR, Slattery KM, Sculley DV, Dascombe BJ

 

Abstract

 

It is generally believed that optimal hypertrophic and strength gains are induced through moderate- or high-intensity resistance training, equivalent to at least 60% of an individual's 1-repetition maximum (1RM). However, recent evidence suggests that similar adaptations are facilitated when low-intensity resistance exercise (~20-50% 1RM) is combined with blood flow restriction (BFR) to the working muscles.

 

Although the mechanisms underpinning these responses are not yet firmly established, it appears that localized hypoxia created by BFR may provide an anabolic stimulus by enhancing the metabolic and endocrine response, and increase cellular swelling and signalling function following resistance exercise.

 

Moreover, BFR has also been demonstrated to increase type II muscle fibre recruitment during exercise. However, inappropriate implementation of BFR can result in detrimental effects, including petechial haemorrhage and dizziness. Furthermore, as BFR is limited to the limbs, the muscles of the trunk are unable to be trained under localized hypoxia.

 

More recently, the use of systemic hypoxia via hypoxic chambers and devices has been investigated as a novel way to stimulate similar physiological responses to resistance training as BFR techniques. While little evidence is available, reports indicate that beneficial adaptations, similar to those induced by BFR, are possible using these methods. The use of systemic hypoxia allows large groups to train concurrently within a hypoxic chamber using multi-joint exercises.

 

However, further scientific research is required to fully understand the mechanisms that cause augmented muscular changes during resistance exercise with a localized or systemic hypoxic stimulus.

 

PMID: 24715613

DOI: 10.1007/s40279-014-0177-7

 

 

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Thank you for your support!

Snippit is made possible by listeners like you.

Please help support the podcast:

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Now that we are a few episodes in, we’ve had some great interactions with listeners. Some of the feedback received was that although the information in the papers that we spoke about was fantastic, the underlying mechanisms and information behind these papers would be beneficial.  One of the areas that we've had a great response to is Blood Flow Restriction training.  Hence, our first Snippit is on the use of localised (BFR) versus systemic (hypoxic chamber) hypoxia for resistance training. We enjoy your interactions and comments so please keep them coming. 

 

Sports Med. 2014 Aug; 44(8):1037-54

https://link.springer.com/article/10.1007%2Fs40279-014-0177-7

 

Hypoxia and resistance exercise: a comparison of localized and systemic methods.

Scott BR, Slattery KM, Sculley DV, Dascombe BJ

 

Abstract

 

It is generally believed that optimal hypertrophic and strength gains are induced through moderate- or high-intensity resistance training, equivalent to at least 60% of an individual's 1-repetition maximum (1RM). However, recent evidence suggests that similar adaptations are facilitated when low-intensity resistance exercise (~20-50% 1RM) is combined with blood flow restriction (BFR) to the working muscles.

 

Although the mechanisms underpinning these responses are not yet firmly established, it appears that localized hypoxia created by BFR may provide an anabolic stimulus by enhancing the metabolic and endocrine response, and increase cellular swelling and signalling function following resistance exercise.

 

Moreover, BFR has also been demonstrated to increase type II muscle fibre recruitment during exercise. However, inappropriate implementation of BFR can result in detrimental effects, including petechial haemorrhage and dizziness. Furthermore, as BFR is limited to the limbs, the muscles of the trunk are unable to be trained under localized hypoxia.

 

More recently, the use of systemic hypoxia via hypoxic chambers and devices has been investigated as a novel way to stimulate similar physiological responses to resistance training as BFR techniques. While little evidence is available, reports indicate that beneficial adaptations, similar to those induced by BFR, are possible using these methods. The use of systemic hypoxia allows large groups to train concurrently within a hypoxic chamber using multi-joint exercises.

 

However, further scientific research is required to fully understand the mechanisms that cause augmented muscular changes during resistance exercise with a localized or systemic hypoxic stimulus.

 

PMID: 24715613

DOI: 10.1007/s40279-014-0177-7

 

 

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This is one of many papers from Prof. Christian Cook and Co.  On many levels, these papers encapsulate the pragmatic application of sports science in the elite training environment:

 

Journal of Science and Medicine in Sport

Volume 17, Issue 3, May 2014, Pages 317-321

 

Morning based strength training improves afternoon physical performance in rugby union players

 

Christian J. Cook

Liam P. Kilduff

Blair T. Crewther

Martyn Beaven

Daniel J. West

 

https://doi.org/10.1016/j.jsams.2013.04.016

 

Abstract

 

Objectives

To determine if a morning training session could alter afternoon physical performance. Moreover, as testosterone (T) and cortisol (C) concentrations are significant predictors of physical performance, and both show circadian declines across the day, we examined the effects of morning training on diurnal T and C responses.

 

Design

Eighteen semi-professional rugby union players completed this randomised and counter-balanced study.

 

Methods

Following morning saliva collection (0900 h), players completed a control (rested), Sprint (5 × 40 m) or Weights (3 repetition-maximum [RM] bench press and squat) trial. In the afternoon (15:00 h) of each trial, a further saliva sample was collected before players completed a performance test (3RM back squat and bench press, 40 m sprint, countermovement jump [CMJ]).

 

Results

Salivary T concentrations declined from am to pm under Control and Sprint, but not under Weights. Delta T, from am to pm, was greater under Control (−10.9 ± 2.4 pg ml−1) compared to Sprints (−6.2 ± 7.1 pg ml−1) and Weights (−1.2 ± 5.5 pg ml−1) (p ≤ 0.001). Delta C, from am to pm, was greater under Control compared to both Sprint and Weights (p

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The Journal of Physiology

Volume 595, Issue 24

 

Post‐exercise recovery of contractile function and endurance in humans and mice is accelerated by heating and slowed by cooling skeletal muscle

 

Arthur J. Cheng 

Sarah J. Willis 

Christoph Zinner 

Thomas Chaillou 

Niklas Ivarsson 

Niels Ørtenblad 

Johanna T. Lanner 

Hans‐Christer Holmberg 

Håkan Westerblad

 

First published: 04 October 2017

https://doi.org/10.1113/JP274870

Linked articles: This article is highlighted by a Perspective by Allen. To read this Perspective, visit https://doi.org/10.1113/JP275370.

Edited by: Michael C. Hogan & Bruno Grassi

 

Key points

We investigated whether intramuscular temperature affects the acute recovery of exercise performance following fatigue‐induced by endurance exercise.

Mean power output was better preserved during an all‐out arm‐cycling exercise following a 2 h recovery period in which the upper arms were warmed to an intramuscular temperature of ̴ 38°C than when they were cooled to as low as 15°C, which suggested that recovery of exercise performance in humans is dependent on muscle temperature.

Mechanisms underlying the temperature‐dependent effect on recovery were studied in intact single mouse muscle fibres where we found that recovery of submaximal force and restoration of fatigue resistance was worsened by cooling (16–26°C) and improved by heating (36°C).

Isolated whole mouse muscle experiments confirmed that cooling impaired muscle glycogen resynthesis.

We conclude that skeletal muscle recovery from fatigue‐induced by endurance exercise is impaired by cooling and improved by heating, due to changes in glycogen resynthesis rate.

 

Abstract

Manipulation of muscle temperature is believed to improve post‐exercise recovery, with cooling being especially popular among athletes. However, it is unclear whether such temperature manipulations actually have positive effects. Accordingly, we studied the effect of muscle temperature on the acute recovery of force and fatigue resistance after endurance exercise.

One hour of moderate‐intensity arm cycling exercise in humans was followed by 2 h recovery in which the upper arms were either heated to 38°C, not treated (33°C), or cooled to ∼15°C. Fatigue resistance after the recovery period was assessed by performing 3 × 5 min sessions of all‐out arm cycling at physiological temperature for all conditions (i.e. not heated or cooled).

Power output during the all‐out exercise was better maintained when muscles were heated during recovery, whereas cooling had the opposite effect. Mechanisms underlying the temperature‐dependent effect on recovery were tested in mouse intact single muscle fibres, which were exposed to ∼12 min of glycogen‐depleting fatiguing stimulation (350 ms tetani given at 10 s interval until force decreased to 30% of the starting force). Fibres were subsequently exposed to the same fatiguing stimulation protocol after 1–2 h of recovery at 16–36°C. Recovery of submaximal force (30 Hz), the tetanic myoplasmic free [Ca2+] (measured with the fluorescent indicator indo‐1), and fatigue resistance were all impaired by cooling (16–26°C) and improved by heating (36°C). In addition, glycogen resynthesis was faster at 36°C than 26°C in whole flexor digitorum brevis muscles.

We conclude that recovery from exhaustive endurance exercise is accelerated by raising and slowed by lowering muscle temperature. 

 

 

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Here is this is one of many papers from Prof. Christian Cook and Co.  We love reading these types of papers as they are really applied and use elite athletes:

 

Changes in salivary testosterone concentrations and subsequent voluntary squat performance following the presentation of short video clips

Christian J. Cook

Blair T. Crewther

 

https://doi.org/10.1016/j.yhbeh.2011.09.006

 

Abstract

Previous studies have shown that visual images can produce rapid changes in testosterone concentrations.

 

We explored the acute effects of video clips on salivary testosterone and cortisol concentrations and subsequent voluntary squat performance in highly trained male athletes (n = 12). Saliva samples were collected on 6 occasions immediately before and 15 min after watching a brief video clip (approximately 4 min in duration) on a computer screen. The watching of a sad, erotic, aggressive, training motivational, humorous or a neutral control clip was randomised. Subjects then performed a squat workout aimed at producing a 3 repetition maximum (3RM) lift.

 

Significant (P

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Nutritional strategies of high level natural bodybuilders during competition preparation

J. Chappell

Simper

E. Barker

 

Journal of the International Society of Sports Nutrition 2018 15:4

https://doi.org/10.1186/s12970-018-0209-z

© The Author(s). 2018

Published: 15 January 2018

 

Abstract

 

Background

Competitive bodybuilders employ a combination of resistance training, cardiovascular exercise, calorie reduction, supplementation regimes and peaking strategies in order to lose fat mass and maintain fat free mass. Although recommendations exist for contest preparation, applied research is limited and data on the contest preparation regimes of bodybuilders are restricted to case studies or small cohorts. Moreover, the influence of different nutritional strategies on competitive outcome is unknown.

 

Methods

Fifty-one competitors (35 male and 16 female) volunteered to take part in this project. The British Natural Bodybuilding Federation (BNBF) runs an annual national competition for high level bodybuilders; competitors must qualify by winning at a qualifying events or may be invited at the judge’s discretion. Competitors are subject to stringent drug testing and have to undergo a polygraph test. Study of this cohort provides an opportunity to examine the dietary practices of high level natural bodybuilders. We report the results of a cross-sectional study of bodybuilders competing at the BNBF finals. Volunteers completed a 34-item questionnaire assessing diet at three time points. At each time point participants recorded food intake over a 24-h period in grams and/or portions. Competitors were categorised according to contest placing. A “placed” competitor finished in the top 5, and a “Non-placed” (DNP) competitor finished outside the top 5. Nutrient analysis was performed using Nutritics software. Repeated measures ANOVA and effect sizes (Cohen’s d) were used to test if nutrient intake changed over time and if placing was associated with intake.

 

Results

Mean preparation time for a competitor was 22 ± 9 weeks. Nutrient intake of bodybuilders reflected a high-protein, high-carbohydrate, low-fat diet. Total carbohydrate, protein and fat intakes decreased over time in both male and female cohorts (P

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Early Hum Dev. 2016 Sep; 100:21-5

https://www.sciencedirect.com/science/article/pii/S0378378216300123

Epub 2016 Jul 6

 

Digit ratio (2D:4D), testosterone, cortisol, aggression, personality and hand-grip strength: Evidence for prenatal effects on strength.

Ribeiro E Jr, Neave N, Morais RN, Kilduff L, Taylor SR, Butovskaya M, Fink B, Manning JT

 

Abstract

 

BACKGROUND:

Digit ratio (2D:4D) is a putative marker for prenatal testosterone and is correlated with performance in many sports. Low 2D:4D has been linked to strength but the evidence is mixed and strength is also influenced by mass, testosterone, and behavioural factors. It has been hypothesised that the 2D:4D-strength correlation may be strongest in challenge conditions when short-term changes occur in steroid hormones.

 

AIMS:

We tested this suggestion in men.

 

STUDY DESIGN:

We used a cross-over study design with a challenge (an aggressive video of rugby tackles) and control (a blank screen) condition.

 

SUBJECTS:

89 healthy men.

 

OUTCOME MEASURES:

Finger lengths (2nd and 4th for both hands), hand-grip strength (HGS), testosterone (T), cortisol (C), aggression (Buss-Perry Aggression Questionnaire) and personality type (Ten Item Personality Measure). In both conditions participants provided saliva samples (for hormone assays).

 

RESULTS:

In the challenge condition there was a highly significant increase in HGS, and modest changes in T, physical aggression and emotional stability. HGS correlated negatively with left hand 2D:4D. In a multiple regression, left hand 2D:4D was negatively related to HGS and emotional stability was positively related to HGS. In the control condition HGS was not correlated with 2D:4D. In a multiple regression, BMI, physical aggression, and emotional stability were significantly related to HGS.

 

CONCLUSIONS:

2D:4D is a negative correlate of strength in challenge situations. This finding may in part explain associations between 2D:4D and sports performance.

 

Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

 

KEYWORDS:

Aggression; Digit ratio; Hand-grip strength; Testosterone

 

PMID: 27393866

DOI: 10.1016/j.earlhumdev.2016.04.003

 

 

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