Search Results

You are looking at 1 - 6 of 6 items for

  • Author: Johann C. Bilsborough x
Clear All Modify Search
Restricted access

Johann C. Bilsborough, Kate Greenway, Steuart Livingston, Justin Cordy and Aaron J. Coutts

The purpose of this study was to examine the seasonal changes in body composition, nutrition, and upper-body (UB) strength in professional Australian Football (AF) players. The prospective longitudinal study examined changes in anthropometry (body mass, fat-free soft-tissue mass [FFSTM], and fat mass) via dual-energy X-ray absorptiometry 5 times during an AF season (start preseason, midpreseason, start season, midseason, end season) in 45 professional AF players. Dietary intakes and strength (bench press and bench pull) were also assessed at these time points. Players were categorized as experienced (>4 y experience, n = 23) or inexperienced (<4 y experience, n = 22). Fat mass decreased during the preseason but was stable through the in-season for both groups. %FFSTM was increased during the preseason and remained constant thereafter. UB strength increased during the preseason and was maintained during the in-season. Changes in UB FFSTM were related to changes in UB-strength performance (r = .37−.40). Total energy and carbohydrate intakes were similar between the experienced and inexperienced players during the season, but there was a greater ratio of dietary fat intake at the start-preseason point and an increased alcohol, reduced protein, and increased total energy intake at the end of the season. The inexperienced players consumed more fat at the start of season and less total protein during the season than the experienced players. Coaches should also be aware that it can take >1 y to develop the appropriate levels of FFSTM in young players and take a long-term view when developing the physical and performance abilities of inexperienced players.

Restricted access

Alexandre Moreira, Johann C. Bilsborough, Courtney J. Sullivan, Michael Cianciosi, Marcelo Saldanha Aoki and Aaron J. Coutts

Purpose:

To examine the training periodization of an elite Australian Football team during different phases of the season.

Methods:

Training-load data were collected during 22 wk of preseason and 23 wk of in-season training. Training load was measured using the session rating of perceived exertion (session-RPE) for all training sessions and matches from 44 professional Australian Football players from the same team. Training intensity was divided into 3 zones based on session-RPE (low, <4; moderate, >4 AU and <7 AU; and high, >7 AU). Training load and intensity were analyzed according to the type of training session completed.

Results:

Higher training load and session duration were undertaken for all types of training sessions during the preseason than in-season (P < .05), with the exception of “other” training (ie, re/prehabilitation training, cross-training, and recovery activities). Training load and intensity were higher during the preseason, with the exception of games, where greater load and intensity were observed during the in-season. The overall distribution of training intensity was similar between phases with the majority of training performed at moderate or high intensity.

Conclusions:

The current findings may allow coaches and scientists to better understand the characteristics of Australian Football periodization, which in turn may aid in developing optimal training programs. The results also indicate that a polarized training-intensity distribution that has been reported in elite endurance athletes does not occur in professional Australian Football.

Restricted access

Sebastien Racinais, Martin Buchheit, Johann Bilsborough, Pitre C. Bourdon, Justin Cordy and Aaron J. Coutts

Purpose:

To examine the physiological and performance responses to a heat-acclimatization camp in highly trained professional team-sport athletes.

Methods:

Eighteen male Australian Rules Football players trained for 2 wk in hot ambient conditions (31–33°C, humidity 34–50%). Players performed a laboratory-based heat-response test (24-min walk + 24 min seated; 44°C), a YoYo Intermittent Recovery Level 2 Test (YoYoIR2; indoor, temperate environment, 23°C) and standardized training drills (STD; outdoor, hot environment, 32°C) at the beginning and end of the camp.

Results:

The heat-response test showed partial heat acclimatization (eg, a decrease in skin temperature, heart rate, and sweat sodium concentration, P < .05). In addition, plasma volume (PV, CO rebreathing, +2.68 [0.83; 4.53] mL/kg) and distance covered during both the YoYoIR2 (+311 [260; 361] m) and the STD (+45.6 [13.9; 77.4] m) increased postcamp (P < .01). None of the performance changes showed clear correlations with PV changes (r < .24), but the improvements in running STD distance in hot environment were correlated with changes in hematocrit during the heat-response test (r = –.52, 90%CI [–.77; –.12]). There was no clear correlation between the performance improvements in temperate and hot ambient conditions (r < .26).

Conclusion:

Running performance in both hot and temperate environments was improved after a football training camp in hot ambient conditions that stimulated heat acclimatization. However, physiological and performance responses were highly individual, and the absence of correlations between physical-performance improvements in hot and temperate environments suggests that their physiological basis might differ.

Restricted access

Courtney Sullivan, Johann C. Bilsborough, Michael Cianciosi, Joel Hocking, Justin T. Cordy and Aaron J. Coutts

Objectives:

To determine the physical activity measures and skill-performance characteristics that contribute to coaches’ perception of performance and player performance rank in professional Australian Football (AF).

Design:

Prospective, longitudinal.

Methods:

Physical activity profiles were assessed via microtechnology (GPS and accelerometer) from 40 professional AF players from the same team during 15 Australian Football League games. Skill-performance measure and player-rank scores (Champion Data Rank) were provided by a commercial statistical provider. The physical-performance variables, skill involvements, and individual player performance scores were expressed relative to playing time for each quarter. A stepwise multiple regression was used to examine the contribution of physical activity and skill involvements to coaches’ perception of performance and player rank in AF.

Results:

Stepwise multiple-regression analysis revealed that 42.2% of the variance in coaches’ perception of a player’s performance could be explained by the skill-performance characteristics (player rank/min, effective kicks/min, pressure points/min, handballs/min, and running bounces/min), with a small contribution from physical activity measures (accelerations/min) (adjusted R 2 = .422, F 6,282 = 36.054, P < .001). Multiple regression also revealed that 66.4% of the adjusted variance in player rank could be explained by total disposals/min, effective kicks/min, pressure points/min, kick clangers/min, marks/min, speed (m/min), and peak speed (adjusted R 2 = .664, F 7,281 = 82.289, P < .001). Increased physical activity throughout a match (speed [m/min] β – 0.097 and peak speed β – 0.116) negatively affects player rank in AF.

Conclusions:

Skill performance rather than increased physical activity is more important to coaches’ perception of performance and player rank in professional AF.

Restricted access

Davide Ferioli, Andrea Bosio, Johann C. Bilsborough, Antonio La Torre, Michele Tornaghi and Ermanno Rampinini

Purpose: To investigate the effect of the preparation period on neuromuscular characteristics of 12 professional (PRO) and 16 semiprofessional (SEMIPRO) basketball players and relationships between training-load indices and changes in neuromuscular physical performance. Methods: Before and after the preparation period, players underwent a countermovement jump (CMJ) test followed by a repeated change-of-direction (COD) test consisting of 4 levels with increasing intensities. The peripheral neuromuscular functions of the knee extensors (peak torque [PT]) were measured using electrical stimulations after each level (PT1, PT2, PT3, and PT4). Furthermore, PT Max (the highest value of PT) and PT Dec (PT decrement from PT Max to PT4) were calculated. Results: Trivial to small (effect size [ES] = −0.17 to 0.46) improvements were found in CMJ variables, regardless of competitive level. After the preparation period, peripheral fatigue induced by a COD test was similarly reduced in both PRO (PT Dec: from 27.8% [21.3%] to 11.4% [13.7%]; ES = −0.71; 90% confidence interval [CI], ±0.30) and SEMIPRO (PT Dec: from 26.1% [21.9%] to 10.2% [8.2%]; ES = −0.69; 90% CI, ±0.32). Moderate to large relationships were found between session rating of perceived exertion training load and changes in peak power output (PPO) measured during the CMJs (r s [90% confidence interval]: PPOabs, −.46 [±.26]; PPOrel, −.53 [±.23]) and in some PTs measured during the COD test (PT1, −.45 [±.26]; PT2, −.44 [±.26]; PT3, −.40 [±.27]; and PT Max, −.38 [±.28]). Conclusions: The preparation period induced minimal changes in the CMJ, while the ability to sustain repeated COD efforts was improved. Reaching high session rating of perceived exertion training loads might partially and negatively affect the ability to produce strength and power.

Restricted access

Johann C. Bilsborough, Thomas Kempton, Kate Greenway, Justin Cordy and Aaron J. Coutts

Purpose:

To compare development and variations in body composition of early-, mid-, and late-career professional Australian Football (AF) players over 3 successive seasons.

Methods:

Regional and total-body composition (body mass [BM], fat mass [FM], fat-free soft-tissue mass [FFSTM], and bone mineral content [BMC]) were assessed 4 times, at the same time of each season—start preseason (SP), end preseason (EP), midseason (MS), and end season (ES)—from 22 professional AF players using pencil-beam dual-energy X-ray absorptiometry. Nutritional intake for each player was evaluated concomitantly using 3-d food diaries. Players were classified according to their age at the beginning of the observational period as either early- (<21 y, n = 8), mid- (21 to 25 y, n = 9), or late- (>25 y, n = 5) career athletes.

Results:

Early-career players had lower FFSTM, BMC, and BM than mid- and late-career throughout. FM and %FM had greatest variability, particularly in the early-career players. FM reduced and FFSTM increased from SP to EP, while FM and FFSTM decreased from EP to MS. FM increased and FFSTM decreased from MS to ES, while FM and FFSTM increased during the off-season.

Conclusions:

Early-career players may benefit from greater emphasis on specific nutrition and resistance-training strategies aimed at increasing FFSTM, while all players should balance training and diet toward the end of season to minimize increases in FM.