Chris Talbot

Predicted maximal heart rate for upper body exercise testing

Age‐predicted maximal heart rate (HRMAX) equations are commonly used for the purpose of prescribing exercise regimens, as criteria for achieving maximal exertion and for diagnostic exercise testing. Despite the growing popularity of upper body exercise in both healthy and clinical settings, no recommendations are available for exercise modes using the smaller upper body muscle mass. The purpose of this study was to determine how well commonly used age‐adjusted prediction equations for HRMAX estimate actual HRMAX for upper body exercise in healthy young and older adults. A total of 30 young (age: 20 ± 2 years, height: 171·9 ± 32·8 cm, mass: 77·7 ± 12·6 kg) and 20 elderly adults (age: 66 ± 6 years, height: 162 ± 8·1 cm, mass: 65·3 ± 12·3 kg) undertook maximal incremental exercise tests on a conventional arm crank ergometer. Age‐adjusted maximal heart rate was calculated using prediction equations based on leg exercise and compared with measured HRMAX data for the arms. Maximal HR for arm exercise was significantly overpredicted compared with age‐adjusted prediction equations in both young and older adults. Subtracting 10–20 beats min−1 from conventional prediction equations provides a reasonable estimate of HRMAX for upper body exercise in healthy older and younger adults.

Stretch imposed on active muscle elicits positive adaptations in strain risk factors and exercise-induced muscle damage

Stretching highly‐contracted plantar flexor muscles (isokinetic eccentric contractions) results in beneficial adaptations in muscle strain risk factors; however its effects in other muscle groups, and on architectural characteristics and exercise‐induced muscle damage (EIMD), are unknown.

Changes in postural sway and gait characteristics as a consequence of anterior load carriage

BACKGROUND Anterior load carriage represents a common daily and occupational activity. Carrying loads in front of the body could potentially increase instability during standing and walking. RESEARCH QUESTION This study examined the effects of anterior load carriage on postural sway and gait parameters in healthy adults. METHODS Twenty-nine participants (19 males, 10 females, age = 33.8 ± 12.7 years, height = 1.73 ± 0.07 m, mass = 75.1 ± 13.7 kg) were assessed in four conditions; (1) carrying no load (CON), (2) carrying a load with no added weight (i.e. empty box), (3) carrying a load with 5% body mass, and (4) carrying a load with 10% body mass. Anteroposterior and mediolateral centre of pressure (COP) displacement (cm) and the mean COP velocity (cm s-1) were used to characterise postural sway. Coefficient of variation of the stride length, stride time and double support time were calculated from 1 min of treadmill walking at a preferred pace for gait assessment. RESULTS The addition of the 10% load elicited an increase in anteroposterior COP displacement when compared to CON (d = 1.59), 0% (d = 1.50), and 5% (d = 0.75) (P < 0.001). The addition of the 10% load increased stride time (d = 1.71) and stride length (d = 1.20) variability when compared to CON (P < 0.001). SIGNIFICANCE In summary, the increase in postural sway and gait variability with added weight is dependent on the magnitude of the load, where the greater the load, the greater the effect on static and dynamic stability. Anterior load carriage potentially increases the risk of fall-related injuries.

A Comparison of Two Anaerobic Test Measurement Systems using an Upper Body Wingate Test

This study aimed to compare performance measures acquired by two different Wingate Anaerobic Test systems; Cranlea and Monark. Twenty participants undertook 58 Wingate tests against a 4% body mass resistive load on a cycle ergometer adapted for arm cranking. Corrected peak power output (PP; W) was recorded using 1 rev min–1, 0.5, 1 and 5 s averages and mean power output (MP; W). The Cranlea system recorded the greatest PP (589 ± 267 W) compared with the Monark (546 ± 267 W; P < 0.001). The PP using all other methods was also greater for the Cranlea compared with the Monark system (P < 0.001) with mean differences of 55 ± 18 W for 1 s averages and 22 ± 18 W for MP. Correlations between all PPs were strong (r = 0.99 – 0.97; P < 0.001). In conclusion, although the Cranlea system provides a consistently greater corrected PP it may not be enough to substantially differentiate between systems.