Strength and Dimensional Stability of Cement-bonded Boards Manufactured from Mixture of Ceiba pentandra and Gmelina arborea Sawdust

Cement bonded boards of 6 mm in thickness were produced from the mixture of Ceiba pentandra and Gmelina arborea sawdust. The influence of weight to weight proportion of C. pentandra and G. arborea blended at levels of 100:0, 75:25, 50:50, 25:75 and 0:100 in mass and mixing ratios of cement to wood 2:1 and 3:1 on Modulus of Rupture (MOR), Modulus of Elasticity (MOE) Water Absorption (WA) and Thickness Swelling (TS) properties of the experimental boards were examined for 24 h and 48 h immersion in cold water. The mean values for MOE and MOR were from 2479.50 to 5294.30 N/mm2 and 0.82 N/mm2 to 3.02 N/mm2 respectively, while the mean values for TS and WA after 24 h in cold water were from 0.53% to 7.35% and 14.8% to 52% respectively, whereas after 48 h in cold water immersion the mean values for TS and WA were from 2.37% to 10.48% and 16.5% to 69.5% respectively. It was observed that, increase in G. arborea (75%) to C. pentandra (25%) and mixing ratio 3:1 (cement/wood) was responsible for increase in MOR and MOE and decrease in TS and WA. The result shows that cement-bonded boards can be manufactured from Ceiba pentandra sawdust when mixed at certain blending proportion and ratio.

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Thermoregulatory responses to cold water at different times of day

Journal of Applied Physiology ◽

10.1152/jappl.1999.87.1.243 ◽

1999 ◽

Vol 87 (1) ◽

pp. 243-246 ◽

Cited By ~ 7

Author(s):

John W. Castellani ◽

Andrew J. Young ◽

James E. Kain ◽

Michael N. Sawka

Keyword(s):

Cold Water ◽

Water Immersion ◽

Early Morning ◽

Cold Water Immersion ◽

Time Of Day ◽

Mean Skin Temperature ◽

Mean Body Temperature ◽

Metabolic Heat ◽

Body Temperature Change ◽

The Mean

This study examined how time of day affects thermoregulation during cold-water immersion (CWI). It was hypothesized that the shivering and vasoconstrictor responses to CWI would differ at 0700 vs. 1500 because of lower initial core temperatures (Tcore) at 0700. Nine men were immersed (20°C, 2 h) at 0700 and 1500 on 2 days. No differences ( P > 0.05) between times were observed for metabolic heat production (M˙, 150 W ⋅ m−2), heat flow (250 W ⋅ m−2), mean skin temperature (T sk, 21°C), and the mean body temperature-change in M˙(ΔM˙) relationship. Rectal temperature (Tre) was higher ( P < 0.05) before (Δ = 0.4°C) and throughout CWI during 1500. The change in Tre was greater ( P < 0.05) at 1500 (−1.4°C) vs. 0700 (−1.2°C), likely because of the higher Tre-T skgradient (0.3°C) at 1500. These data indicate that shivering and vasoconstriction are not affected by time of day. These observations raise the possibility that CWI may increase the risk of hypothermia in the early morning because of a lower initial Tcore.

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COMBINATION OF STRETCHING WITH IMMERSION SYSTEM (COLD AND CONTRAST) ON DOMS PAIN TOLERANCE

Sport and Fitness Journal ◽

10.24843/spj.2021.v09.i02.p04 ◽

2021 ◽

Vol 9 (2) ◽

pp. 118

Author(s):

Dewi Sartika

Keyword(s):

Water Temperature ◽

Cold Water ◽

Water Immersion ◽

Cold Water Immersion ◽

Pain Tolerance ◽

Group I ◽

The Mean ◽

Group Ii ◽

Better Than ◽

Tolerance Improvement

Introduction: DOMS is a complaint of muscle pain experienced by athletes by exercising overloadedly. DOMS pain tolerance improvement was carried out with several interventions, in the form of a combination of stretching with cold water immersion, and stretching with contrast water immersion. The purpose of this research is to proving which comparison of physiotherapy interventions is better for DOMS pain tolerance improvement. Method: The research was carried out in the Ngurah Rai athletics field in Denpasar in January 2020, experimental in nature with a pretest and post test two group design. Samples were male athletes divided into two groups, each group consisting of 9 respondens. Group I was given a combination of stretching and cold water immersion, Group II was given a combination of stretching and water immersion in contrast. Cold water temperature is 10 ?C and warm water temperature 36-40 ?C. Pain tolerance value measured by sphygmomanometer placed on the calf. The higher the value mmHg, the higher the tolerance would be. Result: Results in Group I, the mean pain tolerance before intervention was 153 ± 7.76 (mmHg) and the mean after intervention (48 hours) 206 ± 8.32 (mmHg) with p = 0,000 (p <0.05). In Group II, the mean pain tolerance before intervention was 154 ± 8.35 (mmHg) and after intervention (48 hours) 188.4 ± 6.95 (mmHg) with a value of p = 0,000 (p <0.05). This showed a significant increase in pain tolerance in each group. Statistical tests conducted between the two groups also showed significant differences, with a result of p = 0,000 (p <0.05) where the value of pain tolerance in Group I was better than Group II. Conclusions: combination of stretching and cold water immersion is better than the combination of stretching and water immersion in contrast in reducing DOMS. Keywords: Delayed onset muscle soreness; stretching; cold water; contrast water immersion.

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Human thermoregulatory responses during cold water immersion after artificially induced sunburn

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1992.262.4.r617 ◽

1992 ◽

Vol 262 (4) ◽

pp. R617-R623 ◽

Cited By ~ 2

Author(s):

K. B. Pandolf ◽

R. W. Gange ◽

W. A. Latzka ◽

I. H. Blank ◽

A. J. Young ◽

...

Keyword(s):

Skin Temperature ◽

Rectal Temperature ◽

Cold Water ◽

Water Immersion ◽

Cold Water Immersion ◽

The Body ◽

Esophageal Temperature ◽

Mean Skin Temperature ◽

Thermoregulatory Responses ◽

The Mean

Thermoregulatory responses during cold-water immersion (water temperature 22 degrees C) were compared in 10 young men before as well as 24 h and 1 wk after twice the minimal erythemal dose of ultraviolet-B radiation that covered approximately 85% of the body surface area. After 10 min of seated rest in cold water, the mean exercised for 50 min on a cycle ergometer (approximately 51% of maximal aerobic power). Rectal temperature, regional and mean heat flow (hc), mean skin temperature from five sites, and hearrt rate were measured continuously for all volunteers while esophageal temperature was measured for six subjects. Venous blood samples were collected before and after cold water immersion. The mean skin temperature was higher (P less than 0.05) throughout the 60-min cold water exposure both 24 h and 1 wk after sunburn compared with before sunburn. Mean hc was higher (P less than 0.05) after 10 min resting immersion and during the first 10 min of exercise when 24 h postsunburn was compared with presunburn, with the difference attributed primarily to higher hc from the back and chest. While rectal temperature and heart rate did not differ between conditions, esophageal temperature before immersion and throughout the 60 min of cold water immersion was higher (P less than 0.05) when 24 h postsunburn was compared with presunburn. Plasma volume increased (P less than 0.05) after 1 wk postsunburn compared with presunburn, whereas plasma protein concentration was reduced (P less than 0.05). After exercise cortisol was greater (P less than 0.05) 24 h postsunburn compared with either presunburn or 1 wk postsunburn.(ABSTRACT TRUNCATED AT 250 WORDS)

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Thermoregulatory model for immersion of humans in cold water

Journal of Applied Physiology ◽

10.1152/jappl.1988.64.2.719 ◽

1988 ◽

Vol 64 (2) ◽

pp. 719-727 ◽

Cited By ~ 34

Author(s):

P. Tikuisis ◽

R. R. Gonzalez ◽

K. B. Pandolf

Keyword(s):

Body Fat ◽

Present Model ◽

Heat Storage ◽

Initial Rate ◽

Cold Water ◽

Water Immersion ◽

Cold Water Immersion ◽

Central Temperature ◽

Thermoregulatory Model ◽

The Mean

The mathematical models of thermoregulation of Stolwijk and Hardy, and Montgomery were used to develop a model suitable for the simulation of human physiological responses to cold-water immersion. Data were obtained from experiments where 13 healthy male volunteers were totally immersed under resting and nude conditions for 1 h in water temperatures of 20 and 28 degrees C. At these temperatures, the mean measured rectal temperature (Tre) fell by approximately 0.9 and 0.5 degrees C, respectively, yet mean measured metabolic rate (M) rose by approximately 275 and 90 W for the low body fat group (n = 7) and 195 and 45 W for the moderate body fat group (n = 6). To predict the observed Tre and M values, the present model 1) included thermal inputs for shivering from the skin independent of their inclusion with the central temperature to account for the observed initial rapid rise in M, 2) determined a thermally neutral body temperature profile such that the measured and predicted initial values of Tre and M were matched, 3) confined the initial shivering to the trunk region to avoid an overly large predicted initial rate of rectal cooling, and 4) calculated the steady-state convective heat loss by assuming a zero heat storage in the skin compartment to circumvent the acute sensitivity to the small skin-water temperature difference when using conventional methods. The last three modifications are unique to thermoregulatory modeling.

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The Beneficial Effect of Parasympathetic Reactivation on Sympathetic Drive During Simulated Rugby Sevens

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2015-0317 ◽

2016 ◽

Vol 11 (4) ◽

pp. 480-488 ◽

Cited By ~ 3

Author(s):

Jamie Douglas ◽

Daniel J. Plews ◽

Phil J. Handcock ◽

Nancy J. Rehrer

Keyword(s):

Cold Water ◽

Water Immersion ◽

Team Sport ◽

Cold Water Immersion ◽

Average Heart Rate ◽

Performance Task ◽

Parasympathetic Reactivation ◽

Natural Logarithm ◽

Repeated Sprint ◽

The Mean

Purpose:To determine whether a facilitated recovery via cold-water immersion (CWI) after simulated rugby sevens would influence parasympathetic reactivation and repeated-sprint (RS) performance across 6 matches in a 2-d tournament.Methods:Ten male team-sport athletes completed 6 rugby sevens match simulations over 2 d with either postmatch passive recovery (PAS) or CWI in a randomized crossover design. Parasympathetic reactivation was determined via the natural logarithm of the square root of the mean of the sum of the squares of differences between adjacent R-R intervals (ln rMSSD). RS performance was calculated as time taken (s) to complete 6 × 30-m sprints within the first half of each match.Results:There were large increases in postintervention ln rMSSD between CWI and PAS after all matches (ES 90% CL: +1.13; ±0.21). Average heart rate (HR) during the RS performance task (HRAverage RS) was impaired from baseline from match 3 onward for both conditions. However, HRAverage RS was higher with CWI than with PAS (ES 90% CL: 0.58; ±0.58). Peak HR during the RS performance task (HRPeak RS) was similarly impaired from baseline for match 3 onward during PAS and for match 4 onward with CWI. HRPeak RS was very likely higher with CWI than with PAS (ES 90% CL: +0.80; ±0.56). No effects of match or condition were observed for RS performance, although there were moderate correlations between the changes in HRAverage RS (r 90% CL: –0.33; ±0.14), HRPeak RS (r 90% CL: –0.38; ±0.13), and RS performance.Conclusion:CWI facilitated cardiac parasympathetic reactivation after a simulated rugby sevens match. The decline in average and peak HR across matches was partially attenuated by CWI. This decline was moderately correlated with a reduction in RS performance.

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Patient Involvement in Treatment Decision Making Can Help or Hinder Placebo Analgesia

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000179 ◽

2014 ◽

Vol 222 (3) ◽

pp. 165-170 ◽

Cited By ~ 2

Author(s):

Andrew L. Geers ◽

Jason P. Rose ◽

Stephanie L. Fowler ◽

Jill A. Brown

Keyword(s):

Patient Involvement ◽

Cold Water ◽

Prior Experience ◽

Water Immersion ◽

Treatment Decision ◽

Cold Water Immersion ◽

Not Given ◽

Placebo Analgesia ◽

Treatment Decision Making ◽

Immersion Experience

Experiments have found that choosing between placebo analgesics can reduce pain more than being assigned a placebo analgesic. Because earlier research has shown prior experience moderates choice effects in other contexts, we tested whether prior experience with a pain stimulus moderates this placebo-choice association. Before a cold water pain task, participants were either told that an inert cream would reduce their pain or they were not told this information. Additionally, participants chose between one of two inert creams for the task or they were not given choice. Importantly, we also measured prior experience with cold water immersion. Individuals with prior cold water immersion experience tended to display greater placebo analgesia when given choice, whereas participants without this experience tended to display greater placebo analgesia without choice. Prior stimulus experience appears to moderate the effect of choice on placebo analgesia.

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Changes in myocardial myosin heavy chain isoform composition with exercise and post-exercise cold-water immersion

Journal of Muscle Research and Cell Motility ◽

10.1007/s10974-021-09603-z ◽

2021 ◽

Author(s):

Ramzi A. Al-horani ◽

Mukhallad A. Mohammad ◽

Saja Haifawi ◽

Mohammed Ihsan

Keyword(s):

Myosin Heavy Chain ◽

Heavy Chain ◽

Cold Water ◽

Water Immersion ◽

Cold Water Immersion ◽

Post Exercise ◽

Myosin Heavy Chain Isoform

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Recovery strategies implemented by sport support staff of elite rugby players in South Africa

South African Journal of Physiotherapy ◽

10.4102/sajp.v65i1.78 ◽

2009 ◽

Vol 65 (1) ◽

Cited By ~ 6

Author(s):

D.V. Van Wyk ◽

M.I. Lambert

Keyword(s):

Cold Water ◽

Water Immersion ◽

Total Duration ◽

Cold Water Immersion ◽

Support Staff ◽

Medical Support ◽

Cross Sectional ◽

Study Results ◽

Recovery Strategies ◽

Rugby Players

Objective: The main aim of this study was to determine strategies used toaccelerate recovery of elite rugby players after training and matches, asused by medical support staff of rugby teams in South A frica. A secondaryaim was to focus on specifics of implementing ice/cold water immersion asrecovery strategy. Design: A Questionnaire-based cross sectional descriptive survey was used.Setting and Participants: Most (n=58) of the medical support staff ofrugby teams (doctors, physiotherapists, biokineticists and fitness trainers)who attended the inaugural Rugby Medical A ssociation conference linked to the South A frican Sports MedicineA ssociation Conference in Pretoria (14-16th November, 2007) participated in the study. Results: Recovery strategies were utilized mostly after matches. Stretching and ice/cold water immersion were utilized the most (83%). More biokineticists and fitness trainers advocated the usage of stretching than their counter-parts (medical doctors and physiotherapists). Ice/Cold water immersion and A ctive Recovery were the top two ratedstrategies. A summary of the details around implementation of ice/cold water therapy is shown (mean) as utilized bythe subjects: (i) The time to immersion after matches was 12±9 min; (ii) The total duration of one immersion sessionwas 6±6 min; (iii) 3 immersion sessions per average training week was utilized by subjects; (iv) The average water temperature was 10±3 ºC.; (v) Ice cubes were used most frequently to cool water for immersion sessions, and(vi) plastic drums were mostly used as the container for water. Conclusion: In this survey the representative group of support staff provided insight to which strategies are utilizedin South A frican elite rugby teams to accelerate recovery of players after training and/or matches.

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Cold-water immersion following sprint interval training does not alter endurance signaling pathways or training adaptations in human skeletal muscle

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00434.2016 ◽

2017 ◽

Vol 313 (4) ◽

pp. R372-R384 ◽

Cited By ~ 13

Author(s):

James R. Broatch ◽

Aaron Petersen ◽

David J. Bishop

Keyword(s):

Mitochondrial Biogenesis ◽

Molecular Mechanisms ◽

Cold Water ◽

P53 Protein ◽

Water Immersion ◽

Interval Training ◽

Cold Water Immersion ◽

Peroxisome Proliferator ◽

Sprint Interval Training ◽

Single Session

We investigated the underlying molecular mechanisms by which postexercise cold-water immersion (CWI) may alter key markers of mitochondrial biogenesis following both a single session and 6 wk of sprint interval training (SIT). Nineteen men performed a single SIT session, followed by one of two 15-min recovery conditions: cold-water immersion (10°C) or a passive room temperature control (23°C). Sixteen of these participants also completed 6 wk of SIT, each session followed immediately by their designated recovery condition. Four muscle biopsies were obtained in total, three during the single SIT session (preexercise, postrecovery, and 3 h postrecovery) and one 48 h after the last SIT session. After a single SIT session, phosphorylated (p-)AMPK, p-p38 MAPK, p-p53, and peroxisome proliferator-activated receptor-γ coactivator-1α ( PGC-1α) mRNA were all increased ( P < 0.05). Postexercise CWI had no effect on these responses. Consistent with the lack of a response after a single session, regular postexercise CWI had no effect on PGC-1α or p53 protein content. Six weeks of SIT increased peak aerobic power, maximal oxygen consumption, maximal uncoupled respiration (complexes I and II), and 2-km time trial performance ( P < 0.05). However, regular CWI had no effect on changes in these markers, consistent with the lack of response in the markers of mitochondrial biogenesis. Although these observations suggest that CWI is not detrimental to endurance adaptations following 6 wk of SIT, they question whether postexercise CWI is an effective strategy to promote mitochondrial biogenesis and improvements in endurance performance.

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