Fibrin glue improves osteochondral scaffold fixation: study on the human cadaveric knee exposed to continuous passive motion

SummaryObjectiveTo evaluate stability and integrity of bi-layer and three-layer collagen-hydroxyapatite (C-HA) osteochondral scaffolds in a human cadaveric knee exposed to continuous passive motion (CPM) with and without loading and the role of added fibrin glue to improve the press-fit fixation of C-HA scaffolds.DesignOsteochondral lesions (2.0 × 1.5 cm) were chiseled out on both condyles and trochlea in eight human cadaveric knees. A total of 24 bi-layer (5 mm, four in each condyle) or three-layer C-HA scaffolds (8 mm, eight in the trochlea, four in each condyle) were first press-fit implanted and underwent testing with CPM, 90 cycles, 0°–90°. The second set of 24 scaffolds was implanted in cleaned lesions with the addition of fibrin glue. Two knees with fibrin glue fixation were additionally exposed to 15 kg loading, with 30 cycles of CPM, 0°–30°. Then, the knees were reopened and the scaffolds were evaluated using semi-quantitative Drobnic and modified Bekkers scores.ResultsAll but two scaffolds remained in the lesions site throughout CPM. Two implants failed: both were bi-layer osteochondral scaffolds, press-fit implanted at the lateral femoral condyle (LFC). A statistically significant difference was obtained between press-fit and fibrin glue implants with both Drobnic (2.9 ± 0.7 vs 4.3 ± 0.1, P < 0.0005) and Bekkers (3.3 ± 1.0 vs 5.0 ± 0.1, P < 0.0005) scores. Additional knee loading did not affect fibrin glue scaffold fixation or integrity.ConclusionThis cadaveric study showed fibrin glue notably improved bi-layer or three-layer C-HA scaffold press-fit fixation regardless of lesion location. It is therefore recommended that fibrin glue be used during surgery to improve early post-operative C-HA scaffold stability and integrity

Lung diffusion in a 14-day swimming altitude training camp at 1850 meters

Swimming exercise at sea level causes a transient decrease in lung diffusing capacity for carbon monoxide (DLCO). The exposure to hypobaric hypoxia can affect lung gas exchange, and hypoxic pulmonary vasoconstriction may elicit pulmonary oedema. The purpose of this study is to evaluate whether there are changes in DLCO during a 14-day altitude training camp (1850 m) in elite swimmers and the acute effects of a combined training session of swimming in moderate hypoxia and 44-min cycling in acute normobaric severe hypoxia (3000 m). Participants were eight international level swimmers (5 females and 3 males; 17-24 years old; 173.5 ± 5.5 cm; 64.4 ± 5.3 kg) with a training volume of 80 km per week. The single-breath method was used to measure the changes in DLCO and functional gas exchange parameters. No changes in DLCO after a 14-day altitude training camp at 1850 m were detected but a decrease in alveolar volume (VA; 7.13 ± 1.61 vs. 6.50 ± 1.59 L; p = 0.005; d = 0.396) and an increase in the transfer coefficient of the lung for carbon monoxide (KCO; 6.23 ± 1.03 vs. 6.83 ± 1.31 mL·min−1·mmHg−1·L−1; p = 0.038; d = 0.509) after the altitude camp were observed. During the acute hypoxia combined session, there were no changes in DLCO after swimming training at 1850 m, but there was a decrease in DLCO after cycling at a simulated altitude of 3000 m (40.6 ± 10.8 vs. 36.8 ± 11.2 mL·min−1·mmHg−1; p = 0.044; d = 0.341). A training camp at moderate altitude did not alter pulmonary diffusing capacity in elite swimmers, although a cycling session at a higher simulated altitude caused a certain degree of impairment of the alveolar-capillary gas exchange

Severe hypoxic exercise does not impair lung diffusion in elite swimmers

Background: Exercise performed at high-altitude may cause a sub-clinical pulmonary interstitial edema which can worsen gas exchange function. This study aimed to evaluate whether there are changes in alveolar-capillary diffusion after exercise during a short-term exposure to hypobaric hypoxia in elite swimmers. Materials & Methods: Seven elite swimmers [age: 20.4 ± 1.4 years, height: 1.78 ± 10.8 m, body mass (BM): 69.7 ± 11.1 kg] participated in the study. Diffusing capacity of the lungs for carbon monoxide (DLCO), transfer coefficient of carbon monoxide (KCO), pulse oximeter oxygen saturation (SpO2) and heart rate (HR) were measured at sea level at rest (SL-R), and after a short-term hypobaric hypoxia exposure (4,000 m), both at rest (HA-R) and at the end of moderate interval exercise (HA-E). Results: The combined exposure to high-altitude and exercise did not change DLCO from SL-R to HA-R, or HA-E (43.8 ± 9.8 to 41.3 ± 10.5 to 42.4 ± 8.6 ml·min-1·mmHg-1, P = 0.391). As expected, elite swimmers showed large decrease in SpO2 (72 ± 5; P < 0.001) and increase in HR (139 ± 9 beats·min-1; P < 0.003) after HA-E. Conclusions: An acute high-altitude exposure combined with submaximal exercise does not change alveolar-capillary diffusion in elite swimmers

Pain reduction and tolerance of type II undenatured collagen in patients with knee osteoarthritis

Background: Osteoarthritis (OA) is the most common cause of pain and disability in adults. Dietary supplements such as undenatured type II collagen (UC-II) have shown to have some benefits in OA treatment. This study aimed to assess changes in pain levels among knee OA patients treated with UC-II for 6 months. Methods: Patients with knee OA of any grade were given a daily 40 mg dose of UC-II (CondroArtil®) as a dietary supplement for 6 months. Pain levels were measured using the visual analog scale (VAS) before starting UC-II 6 months thereafter. A total of 100 patients (62/38: male/female) with a mean age of 46.3±13.8 years participated in the study. Most patients (60%) had mild to moderate OA (grade I or II). Results: The UC-II supplementation was shown to significantly reduce pain levels (p&lt;0.001) with a negative correlation between pain reduction and age (p=0.006) and BMI (p=0.049). The OA severity also affected pain reduction (p=0.011), with grade II OA experiencing higher pain levels. Previous physical therapy and food supplements had a significant impact on pain reduction (p=0.017 and p=0.012, respectively). Conclusions: The study suggests that UC-II is an effective treatment for reducing pain in patients with knee OA

Krill-Oil-Dependent Increases in HS-Omega-3 Index, Plasma Choline and Antioxidant Capacity in Well-Conditioned Power Training Athletes

There is evidence that both omega-3 polyunsaturated fatty acids (n-3 PUFAs) and choline can influence sports performance, but information establishing their combined effects when given in the form of krill oil during power training protocols is missing. The purpose of this study was therefore to characterize n-3 PUFA and choline profiles after a one-hour period of high-intensity physical workout after 12 weeks of supplementation. Thirty-five healthy power training athletes received either 2.5 g/day of Neptune krill oilTM (550 mg EPA/DHA and 150 mg choline) or olive oil (placebo) in a randomized double-blind design. After 12 weeks, only the krill oil group showed a significant HS-Omega-3 Index increase from 4.82 to 6.77% and a reduction in the ARA/EPA ratio (from 50.72 to 13.61%) (p < 0.001). The krill oil group showed significantly higher recovery of choline concentrations relative to the placebo group from the end of the first to the beginning of the second exercise test (p = 0.04) and an 8% decrease in total antioxidant capacity post-exercise versus 21% in the placebo group (p = 0.35). In conclusion, krill oil can be used as a nutritional strategy for increasing the HS-Omega-3 Index, recover choline concentrations and address oxidative stress after intense power trainings

Efficient muscle distribution reflects the positive influence of coenzyme Q10 Phytosome in healthy aging athletes after stressing exercise

Coenzyme Q10 (CoQ10) is an ubiquitously-distributed molecule with a key role in mitochondrial efficiency, involving protection against peroxidation induced by reactive oxygen species. In athletes during intense training and strenuous exercise, a reactive oxygen species overproduction occurs and can cause muscular stress and damage: a reduction of those undesired effects would be of benefit. CoQ10 antioxidant properties are described in several clinical studies, but efficacy of CoQ10 supplementation in pre-senescent athletes has not yet been clearly demonstrated. A randomized, intervention-controlled, single-center clinical trial was performed in healthy aging (pre-senescent) runners undergoing exercise training in conditions of high environmental stress. One group used an innovative food-grade CoQ10 phytosome formulation (Ubiqsome) daily for 30 days, while the control group did not take supplementation. Phytosome technique applied to CoQ10 successfully increased CoQ10 bioavailability, as previously demonstrated. CoQ10 levels and oxidative with inflammatory markers were detected in both plasma and muscle. Data obtained highlighted that 500 mg of CoQ10 phytosome (corresponding to 100 mg CoQ10), administered once a day for 30 days significantly improved CoQ10 bioavailability in healthy volunteer aging runners (50-65 years) by increasing both plasmatic and muscular CoQ10 levels, with a reduction of inflammatory cytokines and Malonyl Dialdehyde levels suggesting a protective effect induced by supplementation. The original CoQ10 phytosome formulation results to be of benefit in increasing CoQ10 plasmatic and muscular levels when CoQ10 decrease occurred for oxidative stress conditions, aging or high training

Calorie restriction improves physical performance and modulates the antioxidant and inflammatory responses to acute exercise

Our aim was to characterize the effects of calorie restriction on the anthropometric characteristics and physical performance of sportsmen and to evaluate the effects of calorie restriction and acute exercise on mitochondria energetics, oxidative stress, and inflammation. Twenty volunteer taekwondo practitioners undertook a calorie restriction of 30-40% on three alternate days a week for one month. Eleven volunteer sportsmen participated as controls. Both groups performed an energy effciency test to evaluate physical performance, and samples were taken before and after exercise. The total weight of participants significantly decreased (5.9%) after calorie restriction, while the effciency of work and the contributions of fat to obtain energy were enhanced by calorie restriction. No significant differences induced by acute exercise were observed in individual non-esterified fatty acid percentage or oxidative stress markers. Calorie restriction downregulated the basal gene expression of nitric oxide synthase, antioxidant enzymes, mitochondrial uncoupling proteins, and repairing stress proteins, but it enhanced the expression of sirtuins in peripheral blood mononuclear cells. In conclusion, one month of calorie restriction decreases body weight and increases physical performance, enhancing energy effciency, moderating the antioxidant and inflammatory basal gene expression, and influencing its response to acute exercise

Exercise-induced bronchoconstriction and atopy in Tunisian athletes

<p>Abstract</p> <p>Background</p> <p>This study is a cross sectional analysis, aiming to evaluate if atopy is as a risk factor for exercise induced bronchoconstriction (EIB) among Tunisian athletes.</p> <p>Methods</p> <p>Atopy was defined by a skin prick test result and EIB was defined as a decrease of at least 15% in forced expiratory volume in one second (FEV1) after 8-min running at 80–85% HRmaxTheo. The study population was composed of 326 athletes (age: 20.8 ± 2.7 yrs – mean ± SD; 138 women and 188 men) of whom 107 were elite athletes.</p> <p>Results</p> <p>Atopy was found in 26.9% (88/326) of the athletes. Post exercise spirometry revealed the presence of EIB in 9.8% of the athletes including 13% of the elite athletes. Frequency of atopy in athletes with EIB was significantly higher than in athletes without EIB [62.5% vs 23.1%, respectively].</p> <p>Conclusion</p> <p>This study showed that atopic Tunisian athletes presented a higher risk of developing exercise induced bronchoconstriction than non-atopic athletes.</p

Effect of Acute Exposure to Moderate Altitude on Muscle Power: Hypobaric Hypoxia vs. Normobaric Hypoxia

When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest Pmean obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to Pmax (~3%) and maximal strength (1RM) (~6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on Pmean and Ppeak in the middle-high part of the curve (≥60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1RM, movement velocity and power during the execution of a force-velocity curve in bench press.This study has been supported by a Grant from the Ministry of education, culture and Sport of Spain, Reference 14/UPB10/07