The current study aimed to show the validity of a portable motion sensor, the SenseWear Armband (SWA), for the estimation of energy expenditure during pole walking. Twenty healthy adults (mean ± SD: age 30.1 ± 7.2 year, body mass 66.1 ± 10.6 kg, height 172.4 ± 8.0 cm, BMI 22.1 ± 2.4 kg·m−2) wore the armband during randomized pole walking activities at a constant speed (1.25 m·s−1) and at seven grades (0%, ±5%, ±15% and ±25%). Estimates of total energy expenditure from the armband were compared with values derived from indirect calorimetry methodology (IC) using a 2–way mixed model ANOVA (Device × Slope), correlation analyses and Bland-Altman plots. Results revealed significant main effects for device, and slope (p < .025) as well as a significant interaction (p < .001). Significant differences between IC and SWA were observed for all conditions (p < .05). SWA generally underestimate the EE values during uphill PW by 0.04 kcal·kg−1·min−1 (p < .05). Whereas, a significant overestimation has been detected during flat and downhill PW by 0.01 and 0.03 kcal·kg−1·min−1 (p < .05), respectively. The Bland-Altman plots revealed bias of the armband compared with the indirect calorimetry at any condition examined. The present data suggest that the armband is not accurate to correctly detect and estimate the energy expenditure during pole walking activities. Therefore, the observed over- and under-estimations warrants more work to improve the ability of SWA to accurately measure EE for these activities.
Gianluca Vernillo, Aldo Savoldelli, Barbara Pellegrini, and Federico Schena
Laurent Mourot, Nicolas Fabre, Aldo Savoldelli, and Federico Schena
To determine the most accurate method based on spectral analysis of heart-rate variability (SA-HRV) during an incremental and continuous maximal test involving the upper body, the authors tested 4 different methods to obtain the heart rate (HR) at the second ventilatory threshold (VT2). Sixteen ski mountaineers (mean ± SD; age 25 ± 3 y, height 177 ± 8 cm, mass 69 ± 10 kg) performed a roller-ski test on a treadmill. Respiratory variables and HR were continuously recorded, and the 4 SA-HRV methods were compared with the gas-exchange method through Bland and Altman analyses. The best method was the one based on a time-varying spectral analysis with high frequency ranging from 0.15 Hz to a cutoff point relative to the individual’s respiratory sinus arrhythmia. The HR values were significantly correlated (r 2 = .903), with a mean HR difference with the respiratory method of 0.1 ± 3.0 beats/min and low limits of agreements (around –6/+6 beats/min). The 3 other methods led to larger errors and lower agreements (up to 5 beats/min and around –23/+20 beats/min). It is possible to accurately determine VT2 with an HR monitor during an incremental test involving the upper body if the appropriate HRV method is used.
Gianluca Vernillo, Aldo Savoldelli, Barbara Pellegrini, and Federico Schena
Accurate assessments of physical activity and energy expenditure (EE) are needed to advance research on positive and negative graded walking.
To evaluate the validity of 2 SenseWear Armband monitors (Pro3 and the recently released Mini) during graded walking.
Twenty healthy adults wore both monitors during randomized walking activities on a motorized treadmill at 7 grades (0%, ±5%, ±15%, and ±25%). Estimates of total EE from the monitors were computed using different algorithms and compared with values derived from indirect calorimetry methodology using a 2-way mixed model ANOVA (Device × Condition), correlation analyses and Bland-Altman plots.
There was no significant difference in EE between the 2 armbands in any of the conditions examined. Significant main effects for device and condition, as well as a consistent bias, were observed during positive and negative graded walking with a greater over- and under-estimation at higher slope.
Both the armbands produced similar EE values and seem to be not accurate in estimation of EE during activities involving uphill and downhill walking. Additional work is needed to understand factors contributing to this discrepancy and to improve the ability of these monitors to accurately measure EE during graded walking.
Federico Schena, Barbara Pellegrini, Cantor Tarperi, Elisa Calabria, Gian Luca Salvagno, and Carlo Capelli
The effect of a prolonged running trial on the energy cost of running (C r) during a 60-km ultramarathon simulation at the pace of a 100-km competition was investigated in 13 men (40.8 ± 5.6 y, 70.7 ± 5.5 kg, 177.5 ± 4.5 cm) and 5 women (40.4 ± 2.3 y, 53.7 ± 4.4 kg, 162.4 ± 4.8 cm) who participated in a 60-km trial consisting of 3 consecutive 20-km laps. Oxygen uptake (VO2) at steady state was determined at constant speed before the test and at the end of each lap; stride length (SL) and frequency and contact time were measured at the same time points; serum creatine kinase (S-CPK) was measured before and at the end of the test. C r in J · kg−1 · m−1, as calculated from VO2ss and respiratory-exchange ratio, did not increase with distance. SL significantly decreased with distance. The net increase in S-CPK was linearly related with the percentage increase of C r observed during the trial. It is concluded that, in spite of increased S-CPK, this effort was not able to elicit any peripheral or central fatigue or biomechanical adaptation leading to any modification of C r.
Maurizio Fanchini, Roberto Ghielmetti, Aaron J. Coutts, Federico Schena, and Franco M. Impellizzeri
To examine the effect of different exercise-intensity distributions within a training session on the session rating of perceived exertion (RPE) and to examine the timing of measure on the rating.
Nineteen junior players (age 16 ± 1 y, height 173 ± 5 cm, body mass 64 ± 6 kg) from a Swiss soccer team were involved in the study. Percentage of heart rate maximum (%HR) and RPE (Borg CR100®) were collected in 4 standardized training sessions (conditions). The Total Quality of Recovery scale (TQR) and a visual analogue scale (VAS) for pain of the lower limbs were used to control for the effect of pretraining fatigue. Every session consisted of three 20-min blocks of different intensities (ie, low-moderate-high) performed in a random order. RPE was collected after every block (RPE5), immediately after the session (RPE-end), and 30 min after the session (RPE30).
RPE5s of each block were different depending on the distribution sequence (P < .0001). RPE-end, TQR, and VAS values were not different between conditions (P = .57, P = .55, and P = .96, respectively). The %HR was significantly different between conditions (P = .008), with condition 3 higher than condition 2 (74.1 vs 70.2%, P = .02). Edwards training loads were not significantly different between conditions (P = .09). RPE30 was not different from RPE-end (P > .05).
The current results show that coaches can design training sessions without concern about the influence of the within-session distribution of exercise intensity on session-RPE and that RPE can be collected at the end of the session or 30 min later.
Gianluca Vernillo, Alfredo Brighenti, Eloisa Limonta, Pietro Trabucchi, Davide Malatesta, Grégoire P. Millet, and Federico Schena
To quantify changes in skeletal-muscle oxygenation and pulmonary O2 uptake (V̇O2) after an extreme ultratrail running bout.
Before (PRE) and after (POST) the race (330-km, 24000 D±), profiles of vastus lateralis muscle oxygenation (ie, oxyhemoglobin [O2Hb], deoxyhemoglobin [HHb], and tissue oxygenation index [TOI]) and V̇O2 were determined in 14 athletes (EXP) and 12 control adults (CON) during two 4-min constant-load cycling bouts at power outputs of 1 (p1) and 1.5 (p1.5) W/kg performed in randomized order.
At POST, normalized [HHb] values increased (p1, +38.0%; p1.5, +27.9%; P < .05), while normalized [O2Hb] (p1, –20.4%; p1.5, –14.4%; P < .05) and TOI (p1, –17.0%; p1.5, –17.7%; P < .05) decreased in EXP. V̇O2 values were similar (P > 0.05). An “overshoot“ in normalized [HHb]:V̇O2 was observed, although the increase was significant only during p1.5 (+58.7%, P = .003). No difference in the aforementioned variables was noted in CON (P > .05).
The concentric and, particularly, the eccentric loads characterizing this extreme ultratrail-running bout may have led to variations in muscle structure and function, increasing the local muscle deoxygenation profile and the imbalance between O2 delivery to working muscles and muscle O2 consumption. This highlights the importance of incorporating graded training, particularly downhill bouts, to reduce the negative influence of concentric and severe eccentric loads to the microcirculatory function and to enhance the ability of runners to sustain such loading.
Nicolas Fabre, Laurent Mourot, Livio Zerbini, Barbara Pellegrini, Lorenzo Bortolan, and Federico Schena
This study tested the hypothesis that the DMAX (for maximal distance) method could be applied to ratings of perceived exertion (RPE), to propose a novel method for individual detection of the lactate threshold (LT) using RPE alone during an incremental test to exhaustion. Twenty-one participants performed an incremental test on a cycle ergometer. At the end of each stage, lactate concentration was measured and the participants estimated RPE using the Borg CR100 scale. The intensity corresponding to the fixed lactate values of 2 or 4 mmol · L−1(2mM and 4mM), the ventilatory threshold (VT), the respiratory-compensation point (RCP), and the instant of equality of pulmonary gas exchange (RER=1.00) were determined. Lactate (DMAX La) and RPE (DMAX RPE) thresholds were determined using the DMAX method. Oxygen uptake (VO2), heart rate, and power output measured at DMAX RPE and at DMAX La were not statistically different. Bland-Altman plots showed small bias and good agreements when DMAX RPE was compared with the DMAX La and RER=1.00 methods (bias = −0.05% and −2% of VO2max, respectively). Conversely, VO2 from the DMAX RPE method was lower than VO2 at 4 mM and at RCP and was higher than VO2 at 2 mM and at VT. VO2 at DMAX RPE was strongly correlated with VO2 at DMAX La (r = .97), at RER=1.00 (r = .97), at 2 mM (r = .85), at 4 mM (r = .93), at VT (r = .95), and at RCP (r = .95). The combination of the DMAX method with the RPE responses permitted precise and individualized estimates of LT using the DMAX method.
Maurizio Fanchini, Ivan Ferraresi, Roberto Modena, Federico Schena, Aaron J. Coutts, and Franco M. Impellizzeri
To examine the construct validity of the session rating perceived exertion (s-RPE) assessed with the Borg CR100 scale to measure training loads in elite soccer and to examine if the CR100 is interchangeable and can provide more-accurate ratings than the CR10 scale.
Two studies were conducted. The validity of the CR100 was determined in 19 elite soccer players (age 28 ± 6 y, height 180 ± 7 cm, body mass 77 ± 6 kg) during training sessions through correlations with the Edwards heart-rate method (study 1). The interchangeability with CR10 was assessed in 78 soccer players (age 19.3 ± 4.1 y, height 178 ± 5.9 cm, body mass 71.4 ± 6.1 kg) through the Bland–Altman method and correlations between change scores in different sessions. To examine whether the CR100 is more finely graded than the CR10, the proportions of responses corresponding to the verbal expressions were calculated (study 2).
Individual correlations between the Edwards method and s-RPE were large to very large (.52–.85). The mean difference between the 2 scales was –0.3 ± 0.33 AU (90% CI –0.41 to –0.29) with 95% limits of agreements (0.31 to –0.96 AU). Correlations between scales and between-changes scores were nearly perfect (.95 and .91–.98). Ratings corresponding to the verbal anchors were 49% in CR10 and 26% in CR100.
The CR100 is valid for assessing the training load in elite soccer players. It can be used interchangeably with the CR10 and may provide more-precise measures of exercise intensity.
Ellen Freiberger, Elisabeth Rydwik, Astrid Chorus, Erwin Tak, Christophe Delecluse, Federico Schena, Nina Waaler, Bob Laventure, and Nico van Meeteren
Within the context of a globally aging population and associated age-related changes to social relationships and individual psycho-physiology, a coalition of mostly European Union (EU) organizations concerned with physical activity in older persons was formed in 2013. The coalition examined worldwide decreases in physical activity among older adults, and the resulting negative effects on health and function for those individuals. After holding expert panel meetings, the coalition developed recommendations about how to address macro- and microlevel changes to increase and sustain physical activity among older populations across Europe. The recommendations were then compiled into a consensus document called “the Rome Statement”, aimed at older adults, policy makers, researchers, and private and public professionals. This article presents the Rome Statement and its recommendations, and discusses how the statement can be broadly disseminated, considered, and implemented.
Francis Degache, Jean-Benoît Morin, Lukas Oehen, Kenny Guex, Guido Giardini, Federico Schena, Guillaume Y. Millet, and Grégoire P. Millet
The aim of study was to examine the effects of the world’s most challenging mountain ultramarathon (Tor des Géants [TdG]) on running mechanics. Mechanical measurements were undertaken in male runners (n = 16) and a control group (n = 8) before (PRE), during (MID), and after (POST) the TdG. Contact (t c) and aerial (t a) times, step frequency (f), and running velocity (v) were sampled. Spring-mass parameters of peak vertical ground-reaction force (F max), vertical downward displacement of the center of mass (Δz), leg-length change (ΔL), and vertical (k vert) and leg (k leg) stiffness were computed. Significant decreases were observed in runners between PRE and MID for t a (P < .001), F max (P < .001), Δz (P < .05), and k leg (P < .01). In contrast, f significantly increased (P < .05) between PRE and MID-TdG. No further changes were observed at POST for any of those variables, with the exception of k leg, which went back to PRE. During the TdG, experienced runners modified their running pattern and spring-mass behavior mainly during the first half. The current results suggest that these mechanical changes aim at minimizing the pain occurring in lower limbs mainly during the eccentric phases. One cannot rule out that this switch to a “safer” technique may also aim to anticipate further damages.