Pritchard, HJ, Barnes, MJ, Stewart, RJC, Keogh, JWL, and McGuigan, MR. Short-term training cessation as a method of tapering to improve maximal strength. J Strength Cond Res 32(2): 458-465, 2018-The aim of this study was to determine the effects of 2 different durations of training cessation on upper- and lower-body maximal strength performance and to investigate the mechanisms underlying performance changes following short-term training cessation. Eight resistance trained males (23.8 ± 5.4 years, 79.6 ± 10.2 kg, 1.80 ± 0.06 m, relative deadlift 1 repetition maximum of 1.90 ± 0.30 times bodyweight [BW]) each completed two 4-week strength training periods followed by either 3.5 days (3.68 ± 0.12 days) or 5.5 days (5.71 ± 0.13 days) of training cessation. Testing occurred pretraining (T1), on the final day of training (T2), and after each respective period of training cessation (T3). Participants were tested for salivary testosterone and cortisol, plasma creatine kinase, psychological profiles, and performance tests (countermovement jump [CMJ], isometric midthigh pull, and isometric bench press [IBP]) on a force plate. Participants' BW increased significantly over time (p = 0.022). The CMJ height and IBP peak force showed significant increases over time (p = 0.013, 0.048, and 0.004, respectively). Post hoc testing showed a significant increase between T1 and T3 for both CMJ height and IBP peak force (p = 0.022 and 0.008 with effect sizes of 0.30 and 0.21, respectively). No other significant differences were seen for any other measures. These results suggest that a short period of strength training cessation can have positive effects on maximal strength expression, perhaps because of decreases in neuromuscular fatigue.

A strength training taper with volume reductions had a positive effect on power, with a tendency for the higher intensity taper to produce more favourable changes in strength and power.

New Zealand (NZ) has one of the world’s highest incidence rates of Inflammatory Bowel Disease (IBD), a group of chronic inflammatory conditions that affect the gastrointestinal tract. Patients with IBD often believe certain foods influence their disease symptoms and consequently may alter their diet considerably. The objective of this study was to determine foods, additives, and cooking methods (dietary elements) that NZ IBD patients identify in the onset, exacerbation, or reduction of their symptoms. A total of 233 participants completed a self-administered questionnaire concerning symptom behaviour in association with 142 dietary elements. Symptom onset and symptom exacerbation were associated with dietary elements by 55% (128) and 70% (164) of all IBD participants, respectively. Fruit and vegetables were most frequently identified, with dairy products, gluten-containing bread, and foods with a high fat content also considered deleterious. Of all IBD participants, 35% (82) associated symptom reduction with dietary elements. The identified foods were typically low in fibre, saturated fatty acids, and easily digestible. No statistically significant differences were seen between the type or number of dietary elements and disease subtype or recent disease activity. The association between diet and symptoms in patients with IBD and the mechanism(s) involved warrant further research and may lead to the development of IBD specific dietary guidelines.

Anecdotally, it is believed that the deadlift exercise brings about greater levels of central fatigue than other exercises; however no empirical evidence exists to support this view. Additionally, little is known about the acute endocrine response to heavy deadlift exercise and how this may differ to other similar compound exercises. Therefore, the aim of this study was to identify and compare the acute, neuromuscular and endocrine responses to squat and deadlift exercise. Ten resistance trained males completed 8 sets of 2 repetitions at 95 % of one repetition maximum. Maximum voluntary isometric knee extensor force (MVIC), along with measures of central (voluntary activation (VA) and surface electromyography (EMG)) and peripheral (electrically evoked control stimulus) fatigue were made prior to and 5 and 30 min post-exercise. Additionally, salivary testosterone and cortisol were measured at these same time points. MVIC was reduced after the completion of both exercises (p = 0.007) however no difference between exercises was evident. Similarly, although VA changed over time (p = 0.0001) no difference was observed between exercises. As a measure of peripheral fatigue, force from the control stimulus changed over time (p = 0.003) with a greater decrease evident after the squat (p = 0.034). EMG was reduced over time (p = 0.048) but no difference was seen between exercises. No change was seen in testosterone and cortisol. Even though a greater absolute load and larger volume-load was completed for the deadlift, no difference in central fatigue was evident between the two compound exercises. The greater peripheral fatigue observed after squat exercise may be due to the greater work completed by the quadriceps with this exercise. These results suggest that separate periodization, tapering and programming considerations may be unnecessary when using the squat and deadlift to develop muscular strength.

Fe bioavailability can be manipulated by the nutritional composition of a meal. Ascorbic acid and unidentified components of meat, fish and poultry, but particularly beef, all appear to enhance the absorption of non-haem Fe. The aim of the present study is to identify whether extracts of green-lipped mussels (GLM; Perna canaliculus) enhance non-haem Fe absorption in Caco-2 cells and to compare the effect with that of beef. Raw GLM and raw beef homogenates were digested in vitro with pepsin at pH 2, and pancreatin and bile salts at pH 7. Tracer 55 Fe was used to measure cellular Fe uptake. Ascorbic acid was used as a positive control and egg albumin, exposed to the same in vitro digestion process, was used as a negative control. Caco-2 cell monolayers were incubated with treatments for 60 min. All values were standardised per mg of GLM, egg albumin, beef or ascorbic acid. The results showed that ascorbic acid enhanced nonhaem Fe absorption to the highest degree. Beef and GLM digestates both significantly enhanced Fe absorption compared with egg albumin. In conclusion, GLM digestate significantly enhances non-haem Fe uptake in Caco-2 cells with a similar magnitude to that of beef.Key words: Iron absorption: Mussels: Caco-2: Meat factor Red meat, pork, poultry and fish all significantly enhance Fe absorption when consumed as part of a vegetable-based meal in human subjects (1) . Further investigation into the bioactive components of meat, poultry and fish factor suggests that cysteine-rich myofibrils (2) , glycosaminoglycans (3) and L-a-glycerophosphocholine (4) could be responsible for this enhancing effect, either individually or in combination (5) . Other dietary factors including PUFA (6) and non-digestible soluble carbohydrates including inulin and fructooligosaccharides (7) may also increase non-haem Fe absorption; however, the magnitude of enhancement and the mechanism remains elusive.Of all meat sources, beef has been repeatedly reported to promote Fe absorption to the highest degree in human subjects (1,4,8) . However, addition of SFA to the diet via increased meat consumption or the replacement of dietary PUFA with SFA is strongly associated with negative cardiovascular outcomes, while the reverse is cardio-protective (9) . For this reason, promoting red meat consumption in order to improve Fe status at a population level may be problematic, and the identification of an alternative meat, poultry and fish factor source rich in PUFA or low in SFA is warranted. The effect of oily fish on Fe uptake has been investigated in vivo; however, protocol inconsistencies have led to contradicting results (6,10,11) .There has been little investigation into the effect of bivalve molluscs on non-haem Fe absorption both in vitro and in vivo. New Zealand green-lipped mussels (GLM, Perna canaliculus) are rich in both haem and non-haem Fe, myofibrillar proteins, low-molecular-weight aminoglycans and n-3 PUFA (12) , and may therefore provide an alternative source of meat factor. The aim of the present study is to inve...

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Static digestion in vitro is a commonly used technique for investigating micronutrient availability which allows the nutrients or foods of interest to be exposed to conditions that simulate those found within the stomach and small intestine. The activity of these digestive enzymes throughout their respective simulated digestion phases has been reported to decline due to the autolytic activity of the proteases and therefore incomplete digestion may result. The degree of protease inactivation under commonly simulated digestion conditions requires further quantification. Pepsin and pancreatic protease activities were assessed throughout a simulated digestion protocol in vitro over multiple time points using stop-rate spectroscopy. The protease activity of both pepsin and pancreatin decreased significantly during their respective digestion phases. Results suggest that gastric and intestinal proteases are destroyed or inactivated during their respective digestive phase. For this reason, prolonged digestion protocols may require protease supplementation throughout digestion to correctly simulate physiological conditions.

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