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Research article
Social support from fellow group members triggers additional effort in groups
JOACHIM HÜFFMEIER
1
*, KATRIN WESSOLOWSKI
2
, ANNETTE VAN RANDENBORGH
3
,
JULIA BOTHIN
2
, NIKOLA SCHMID-LOERTZER
2
AND GUIDO HERTEL
2
1
Federal Institute for Occupational Safety and Health, Dortmund, Germany;
2
Department of Organizational and
Business Psychology, Westfälische Wilhelms-Universität Münster, Germany;
3
Department of Social Studies,
University of Applied Sciences, Münster, Germany
Abstract
This research demonstrates social support from fellow group members as unique trigger of additional effort and performance in
groups. Support-induced effort gains are shown both compared with groups without social support and individual work. Study 1
examined existing beliefs about motivating group work among employees with professional group work experience (n = 130).
The results revealed social support as one of the most frequently reported sources of group-induced effort gains. Study 2 explored
self-reported effort intentions in group training scenarios among athletes (n = 94). Finally, Study 3 examined performance as a
manifest indicator of effort in an experimental persistence task among students (n = 88). The results of Study 2 and Study 3 showed
significant gains due to social support in both self-reported effort and manifest performance, respectively. Together, the results
demonstrate that receiving social support from fellow group members leads to higher effort in groups at the level of existing
beliefs about motivating group work, at the level of effort intentions, and at the level of manifest performance behavior. The observed
findings cannot be explained by established sources of motivation gains in groups such as social comparison or social indispensability.
Copyright © 2014 John Wiley & Sons, Ltd.
What motivates us about group work and pushes us to a higher
level of performance? Extant research investigating beneficial
effects of group work on individual group members’motiva-
tion suggests that we activate additional effort as a function
of contextual characteristics such as task interdependence or
the capability level of fellow group members (e.g., Hüffmeier
& Hertel, 2011; Karau & Williams, 1993; Weber & Hertel,
2007).
1
Specifically, previous research has identified effort
gains for individual group members resulting from social
indispensability—the perception of high instrumentality of
one’s performance for the group outcome (e.g., Hertel, Kerr, &
Messé, 2000), social comparison—the comparison with a more
capable partner (e.g., Stroebe, Diehl, & Abakoumkin, 1996) or
the comparison with members of another group (e.g., Tauer &
Harackiewicz, 2004), and social compensation—the anticipa-
tion of low performance of weaker group members in a valued
task (e.g., Williams & Karau, 1991).
However, the motivating effects of concrete interactions within
groups on individual members have so far been rather neglected.
Research investigating supportive behavior (e.g., altruism and
helping as part of organizational citizenship behaviors; cf. Organ,
1990; L. J. Williams & Anderson, 1991) has generally focused on
the antecedents (e.g., Ilies, Fulmer, Spitzmuller, & Johnson, 2009;
Rioux & Penner, 2001; Smith, Organ, & Near, 1983) but not on
the consequences of supportive behavior. Furthermore, positive
effects of supportive behavior have been predominantly measured
in terms of complex performance outcomes (e.g., performance
evaluations or reward allocation decisions; e.g., Podsakoff,
Whiting, Podsakoff, & Blume, 2009) that limit clear conclusions
about underlying motivational processes. Moreover, these effects
of supportive behavior have been usually examined for the
providers of support but not for the recipients. Initial research with
amorespecific focus on motivational consequences of receiving
support, however, has so far only addressed the negative side, that
is, the demotivating effect of lacking support (e.g., research on
social ostracism; cf. Kerr, Seok, Poulsen, Harris, & Messé,
2008). As the focus of the present research is on group work in
various contexts and settings (e.g., sports or schools) and thus goes
beyond the organizational context, we will subsequently use the
term social support when referring to supportive behaviors.
In the present paper, we extend previous research to moti-
vational consequences of positive interactions in groups and
demonstrate that the reception of social support from fellow
group members is a unique and strong trigger of effort gains
for individuals in groups. First, we document fellow group
members’social support as a significant trigger of additional
effort beyond established sources of effort gains in groups
(i.e., social indispensability, social comparison, and social
*Correspondence to: Joachim Hüffmeier, Federal Institute for Occupational Safety and Health, Friedrich-Henkel-Weg 1-25, 44149 Dortmund, Germany.
E-mail: hueffmeier@uni-muenster.de
1
Motivation as an overarching construct generally refers to effort and direction of behavior (e.g., Geen, 1995). Here, we focus on effort as a consequence of in-
dividual and group conditions, reflecting the intensity and persistence of behavior. Consequently, the term effort gains will be used instead of the less specific term
motivation gains.
European Journal of Social Psychology,Eur. J. Soc. Psychol. (2014)
Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/ejsp.2021
Copyright © 2014 John Wiley & Sons, Ltd. Received 11 October 2013, Accepted 9 March 2014
compensation). Thereby, we enlarge the prevailing focus on
contextual characteristics as sources of effort gains in groups
to interactive processes among group members. Second,
examining different levels of psychological functioning in
separate studies contributes to a more thorough understanding
of the underlying psychological mechanisms of social support
(for a similar approach, see research on organizational citizen-
ship behavior, which has been studied both as concrete
behavior and as willingness to help and cooperate; Chiaburu,
Stoverink, Li, & Zhang, 2013; Joireman, Kamdar, Daniels, &
Duell, 2006). In the current study, we explore the effects of
fellow group members’support at three different levels of
psychological functioning—existing beliefs about motivating
group work, effort intentions in group settings, and perfor-
mance behavior in group tasks. Third, by manipulating
support in an experimental setting, we provide causal evi-
dence for the motivating effects of receiving social support.
We thereby extend previous correlational research on the
motivational effects of supportive behavior (e.g., Chiaburu
& Harrison, 2008). Fourth, we provide initial evidence for
the validity of the Model of Social Support in Teams (MSST;
Hüffmeier & Hertel, 2011) as the general framework of this
research. Finally, we discuss initial practical implications of
our results for the motivation management of groups.
SOCIAL SUPPORT IN GROUPS
Despite the scarcity of systematic research demonstrating a
causal relation, social support seems to be an obvious motivating
mechanism in groups. We often support fellow group members
of our soccer team, our fellow project members at work, or a
fellow student because we implicitly assume that support has a
positive effect on motivation and performance. Indeed, one of
the earliest studies of effort and performance in groups already
described that only few participants stayed unaffected by the
received encouragement from their fellow group partners
(Köhler, 1926, p. 279). However, research has identified several
mechanisms in Köhler’s study that can account for the motivating
effects found (e.g., social comparison or feeling indispensable for
the group; e.g., Kerr & Hertel, 2011). Systematic research that
investigates specifically whether receiving social support can
trigger (i.e., is causally responsible for) higher effort among group
members is lacking. Instead, the provision and reception of social
support has been usually controlled as potential confound in
laboratory studies addressing other sources of motivating effects
in groups (e.g., Hertel et al., 2000; Kerr et al., 2007). Furthermore,
field studies providing correlational evidence for the relationship
between social support and performance (e.g., Beehr, Jex,
Stacy, & Murray, 2000; Osca, Urien, Gonzalez-Camino,
Martinez-Perez, & Martinez-Perez, 2005) lack clear causal
evidence for the obtained effect and might include undiscovered
confounding variables. In addition, positive correlations
between social support and performance do not unambiguously
evidence effort gains of individuals in groups, but might merely
indicate the absence of effort losses (e.g., social loafing; Karau &
Williams, 1993). It thus still remains an open question whether
receiving fellow group members’social support can indeed
trigger additional effort in individual group members (for a
recent study showing lacking effects of social support, see Irwin,
Feltz, & Kerr, 2013), or whether social support is merely a
plausible but factually not effective aspect of group processes,
similar to, for example, brainstorming in groups (cf. Osborn,
1953; Stroebe, Nijstad, & Rietzschel, 2010). In order to advance
research on the dynamics resulting from fellow group members’
social support, it is therefore important to clearly demonstrate
the causal motivational effects of the reception of fellow group
members’support. Moreover, if fellow group members’social
support proves to be as effective in increasing effort as it is
widely assumed, it might be an important yet neglected
instrument for facilitating group work.
Hüffmeier and Hertel (2011) suggested a theoretical model
on the effects of fellow group members’social support on mo-
tivation and performance. In the MSST, the authors conceive
fellow group members as important sources of social support
beyond other influences (e.g., supervisors or organizations;
see also Chiaburu & Harrison, 2008). Group members interact
frequently, know the group task and related challenges well,
and are therefore particularly apt to offer appropriate, in-depth,
and regular support.
Specifically, the MSST distinguishes affective and task-
related social support. Affective social support in general incor-
porates receiving appreciation, care, and emotional strength
from fellow group members (see also Carson, Tesluk, &
Marrone, 2007; Cobb, 1976), and is further classified into social
recognition and social encouragement. Social recognition—
including appreciation, praise, and acknowledgement of
behavior—is directed toward past and/or present perfor-
mance; social encouragement—including the expressed belief
in group members, reassurance, and cheering—is directed
toward future or anticipated performance (Hüffmeier & Hertel,
2011). According to the MSST, affective support should
increase individual effort among group members who receive
such support, leading to effort gains in groups. Effort gains in
groups (or due to teamwork) are defined as higher effort of
persons working in a group as compared with working indi-
vidually (Hertel, 2000; see also Larson, 2009). In contrast,
task-related support includes information about or assistance
with a task and should primarily enhance coordination among
group members. However, receiving task-related support might
also contribute to individual members’effort in groups.
In the present research, we expect motivating effects of re-
ceiving social support on individual group members’effort at
three levels: (a) existing beliefs about motivating group work,
(b) self-reported effort intentions, and (c) manifest perfor-
mance behavior. Group members’beliefs about motivating
group work provide initial insights into motivational processes
in groups as they reflect both personal experience and pre-
scriptive norms that in turn might affect individuals’motiva-
tion and behavior. Group norms, such as in-group and
reciprocity norms (e.g., Gouldner, 1960; Tajfel, 1970; Wilder,
1986) prescribe loyalty and mutual support among group
members. Providing support for and receiving support from
in-group members might thus be salient default expectations
in groups. Furthermore, when considering motivating group
work, people with group work experience might draw on
personal experiences of receiving fellow group members’
support. Social support should thus be salient in people’s
beliefs about motivating group work. In relation to other
Joachim Hüffmeier et al.
Copyright © 2014 John Wiley & Sons, Ltd. Eur. J. Soc. Psychol. (2014)
well-researched triggers of additional effort in groups, we
expect the following:
Hypothesis 1: People with group work experience will
mention social support as a source of effort gains in
groups spontaneously at least as often social indispensa-
bility, social comparison, and social compensation when
being asked about motivating group work.
Furthermore, receiving social support should also affect ef-
fort intentions, which constitute a central precursor of actual
performance and specify the effort people plan to exert in a
subsequent task (cf. Hüffmeier, Dietrich, & Hertel, 2013;
Karau & Williams, 1993). Following from in-group and reci-
procity norms, recipients of social support should be expected
to reciprocate this support by either providing support to other
group members and/or by exerting higher effort for the group.
Thus, recipients of social support should report higher effort
intentions as compared with individuals with no support in
order to reciprocate support and adhere to social norms.
Initial evidence for the motivating effects of social support
was demonstrated in experimental studies of individual work,
showing that support from an experimenter can increase
participants’task performance compared with receiving no
support (e.g., Tardy, 1992). Moreover, field studies revealed
positive correlations between receiving work-related social
support and performance (e.g., Beehr et al., 2000; Chiaburu
& Harrison, 2008; Osca et al., 2005). However, as positive
correlations between social support and performance do not
unambiguously evidence effort gains for individual group
members, it remains unclear whether receiving social support
has indeed triggered effort gains in groups or has just reduced
effort losses. In order to unambiguously demonstrate whether
social support can indeed trigger effort gains in groups, perfor-
mance during group work with social support should be com-
pared against a theory-based and appropriate baseline
condition, for example, individual work (cf. Hertel et al.,
2000; Kerr et al., 2007). Based on the theoretical rationale
outlined previously, we predict the following:
Hypothesis 2: Group members receiving social support
from their fellow members express higher effort inten-
tions as compared with group members receiving no sup-
port or persons working individually.
Furthermore, as effort intentions constitute a central precursor
of actual performance (e.g., Hüffmeier et al., 2013; Karau &
Williams, 1993), we assume that effects of social support also
manifest at the level of factual performance. We thus predict
the following:
Hypothesis 3: Group members receiving social support
from their fellow members exhibit higher effort-
contingent performance than group members receiving
no support or persons working individually.
To study the proposed effects, we first explored the as-
sumed salience of social support in people’s beliefs about mo-
tivating group work in a survey among employees with
professional group work experience in Study 1. In Study 2,
we investigated self-reported effort intentions as precursor of
actual performance employing training scenarios among vol-
leyball players. Finally, in Study 3, we examined actual effort
expenditure with an established persistence task (Hertel et al.,
2000) among student dyads.
STUDY 1
Method
Participants
One hundred and thirty employees with professional group
work experience from various occupational fields (71 women,
58 men; M
(age)
= 39.33, SD = 12.55) voluntarily participated in
this study.
2
Participants were recruited in commuter trains to
survey a sample with a wide range of professions, a broad age
range, and a balanced gender distribution. Participants did not
receive any compensation.
Measures
In a short survey, the participants read the following instruction:
Please remember situations at your job in which you
worked together with others as a group. Please remember
specifically situations in which the work in your group
was so motivating for you that you excelled yourself. What
was decisive for your increased motivation in these situa-
tions? Please name at least three reasons or triggers of addi-
tional motivation through your group.
Focusing on general characteristics of the work environ-
ment and on social support specifically, two raters indepen-
dently coded whether or not participants named
characteristics of the task (e.g., task meaningfulness), of their
fellow group members (e.g., high motivation), of the formal
work organization (e.g., allocation of subtasks), or of interper-
sonal processes between group members (e.g., communica-
tion). Social support constituted a subcategory of
interpersonal processes and was coded as affective support
(e.g., receiving recognition, praise, reassurance, being cheered
on, and cared about) or task-related support (e.g., mutual help
and assistance) following the MSST (Hüffmeier & Hertel,
2011). The intra class correlation (two-way mixed) as a mea-
sure of the agreement between the two raters (Shrout & Fleiss,
1979) was initially .78, 95% confidence interval (CI) [.75,
.81], and increased to .98, 95% CI [.980, .984], after the raters
had discussed incongruent ratings.
Results and Discussion
Results revealed that interpersonal processes were mentioned
by 54.6% of all participants as reasons or triggers of additional
motivation in groups.
3
Among those who mentioned interper-
sonal processes, 49.3% specifically described fellow group
members’social support as experienced trigger of additional
motivation. To test Hypothesis 1, we employed McNemar’s
test (McNemar, 1947). Results indicated that social support
(mentioned 35 times) was mentioned significantly more often
2
One participant did not provide age and gender.
3
Results are reported as means between the two raters.
Social support causes effort gains
Copyright © 2014 John Wiley & Sons, Ltd. Eur. J. Soc. Psychol. (2014)
than social indispensability, the most frequently mentioned
(16 times) of the three often studied triggers of effort gains,
χ
2
(1) = 8.40, p= .005 (cf. Table 1). This result thus provides
empirical evidence for Hypothesis 1 and furthermore indicates
that social support was mentioned more often than all three
often investigated triggers of effort gains (cf. Table 1).
The types of social support mentioned included 74.3%
affective support and 40.0% task-related support (for an over-
view, see Table 1).
4
Thus, in accordance with the MSST
(Hüffmeier & Hertel, 2011), social support and particularly
affective support were frequently perceived as sources of
effort gains in people’s beliefs about motivating group work.
In Study 2, we investigated in a controlled experimental
setting whether receiving affective support, as the hypothe-
sized main source of additional effort (cf. Hüffmeier & Hertel,
2011), can indeed trigger effort gains in groups in terms of
self-reported effort intentions as a direct precursor of behavior.
STUDY 2
Method
Participants
Ninety-four volleyball players (52 women, 42 men; M
(age)
= 26.00,
SD = 13.07) of various amateur sports groups were recruited at a
season opening tournament and received candy as non-monetary
reward.
Experimental Task and Design
Participants completed written questionnaires describing seven
similar line sprint scenarios, which many teams in volleyball
practice perform on a daily base. These line sprints are thus
highly familiar to active players. The first scenario, an
individual sprint, was used as reference point for the
subsequent group sprint scenarios (cf. Hüffmeier et al., 2013).
Group sprints were framed as entailing either no support, social
recognition, or social encouragement from fellow group
members. Social recognition and social encouragement were
realized as separate conditions because the MSST (Hüffmeier
& Hertel, 2011) assumes that both processes are independent
and trigger equally strong effort gains. Furthermore, group
size was incorporated as an exploratory factor in order to
investigate possible effects of the number of supporting
group members on reported effort intentions. In accordance
with Social Impact Theory (Latané, 1981), it could have been
expected that a higher number of sources of social support
increases the impact experienced by the target. We thus
compared a larger number of social support providers (N=6)
with a smaller number of providers of support (N=3). Finally,
to control for order effects, the six group sprint scenarios were
arranged in two different random orders. The experimental
design thus represented a 3 (support: no support vs. social
recognition vs. social encouragement)×2 (group size: three
vs. six players) × 2 (scenario order: order 1 vs. 2) design with
the first two factors being within-subjects.
Procedure
For the individual scenario, participants imagined performing
a line sprint between volleyball court lines twice on their
own. Participants were told that their individual sprinting time
is very important to the coach and would co-determine playing
times (i.e., the desired outcome for motivated volleyball
players). For the group scenarios, participants imagined
performing the line sprints as a relay group. It was described
that group performance would be the sum of the individual
group members’sprinting times and would co-determine
playing times. In the group scenarios operationalizing social
recognition, it was additionally described that the relay group
claps and shouts (“You are running really well! Keep it up!”)
to provide appreciation of and praise for the shown perfor-
mance while the participant is running. In the scenarios
operationalizing social encouragement, it was explained that
prior to the sprint fellow group members cheer the participant
on (“Let’s go! You can do it!”, exchange high fives), to
express belief in him/her and encouragement for future perfor-
mance. Completing the questionnaire took about 30 min.
Measures
After reading each scenario, participants indicated their effort
intentions on two items (“How much effort will you expend
in this run?”and “How much dedication will you show during
this run?”; cf. Hüffmeier et al., 2013). The individual scenario
was not further analyzed as it functioned as the reference for
the group scenarios. For the group scenarios, the 7-point scales
ranged from 1 (much less compared with running individually)
to 7 (much more compared with running individually) with
a scale midpoint of 4.0 termed “as much as when running
individually”(cf. Hüffmeier et al., 2013). For the six group
scenarios, the two items correlated between .83 and .87.
Results
The 3 (support: no support vs. social recognition vs. social
encouragement) × 2 (group size: three vs. six players) × 2
Table 1. Percentages and absolute values for triggers of additional
motivation reported as means between raters (Study 1; N= 130)
Trigger of additional motivation Percentage Absolute value
General
Interpersonal processes
a
54.6 71
Task 41.9 54.5
Group members 43.1 56
Formal work organization 45.8 59.5
Specific
Social support 26.9 35
b
Affective support 20.0 26
Task-related support 10.8 14
Social indispensability 12.3 16
Social comparison 1.9 2.5
Social compensation 0.8 1
Note:
a
Includes social support.
b
Reports the number of people that mentioned at least one type of social
support.
4
As some participants mentioned both types of support, the reported percent-
ages exceed 100 %.
Joachim Hüffmeier et al.
Copyright © 2014 John Wiley & Sons, Ltd. Eur. J. Soc. Psychol. (2014)
(scenario order: order 1 vs. 2) ANOVA of effort intentions re-
vealed a significant main effect for support, F(2, 184) = 26.70,
p<.001, η
2
= .23, indicating differences in effort intentions in
the support conditions. No other main or interaction effects
were found, Fs<1.36, indicating that neither group size nor
scenario order had an effect on effort intentions.
In a more detailed analysis of the main effect of support, we
compared mean levels of intended effort with the scale
midpoint of 4 (“as much as when running individually”).
The scale midpoint represents a theory consistent and clear
baseline to determine group-based effort gains and losses.
Ratings above (below) the scale midpoint indicated intentions
to increase (reduce) one’s effort when running in groups. One
sample t-tests revealed significant increases in effort
intentions for conditions with social recognition (M= 5.80,
SD = 0.94), t(93) = 18.59, p<.001, d= 1.91 and social
encouragement (M=5.76,SD = 0.97), t(93) = 17.55, p<.001,
d= 1.80, supporting Hypothesis 2. As mean ratings of the
social recognition and social encouragement conditions did
not differ significantly, t<1, and correlated highly, r= .81,
p<.001, one general mean score for the conditions comprising
affective support was calculated. A paired t-test showed
significantly higher increases in effort intentions in conditions
with affective support (M=5.78, SD = 0.91) as compared
with group conditions with no support (M= 5.31, SD = 1.02),
t(93) = 6.22, p<.001, d= 0.64, further supporting Hypothesis
2. The post-hoc comparison of the no-support group condition
with the scale midpoint revealed also a significant increase in
effort intentions, t(93) = 12.48, p<.001, d= 1.29, however
this effect was weaker as in the conditions with affective
support. The results thus support the underlying assumption
of the MSST (Hüffmeier & Hertel, 2011) that social recogni-
tion and social encouragement are independent and equally
effective triggers of effort gains in groups.
Discussion
In accordance with Hypothesis 2, we demonstrated that
(imagined) affective social support from fellow group
members increases group members’effort intentions com-
pared with receiving no support or performing individually.
Results are thus in line with the MSST (Hüffmeier & Hertel,
2011) and the assumed in-group and reciprocity norms
(e.g., Gouldner, 1960; Tajfel, 1970; cf. Study 1), which demand
the reciprocation of received support by increased effort.
The observed increases in effort intentions in the no-
support group condition compared with performing individu-
ally can be attributed to a high indispensability for the groups’
success and possibly also to the inter-group competition
with other groups in this exercise (Wittchen, van Dick, &
Hertel, 2011). Importantly, however, receiving social support
increased intended effort well beyond the level of the
no-support group condition.
Self-reported effort intentions are, however, not always
valid predictors of behavior (cf. Ajzen, 1991; Sheeran,
2002). Due to social desirability in the utilized group sport
context or hypothesis guessing that may have resulted from
comparing several group scenarios to one individual scenario,
participants might have reported more favorable ratings for
group work with support. However, social desirability and
social demands present in Study 2 are not confounds that can
or even should be avoided in the context of our research. In-
stead, social demands are part of the process of interest given
that we assume that the motivational effect of social support
is (at least partly) based on social norms. To overcome possi-
ble biases of self-reports and to extend the present findings to
actual effort expenditure, we employed a persistence task with
behavioral performance measures in the third study. Further-
more, to gain first insights into the amount and type of social
support voluntarily provided, we allowed for spontaneous af-
fective and task-related support. This also enabled a first inves-
tigation of the proposed general effect of receiving social
support (including both affective and task-related support) on
group members’effort gains (cf. Hüffmeier & Hertel, 2011).
STUDY 3
Method
Participants
Eighty-nine female participants, M
(age)
= 22.48, SD = 3.05,
mostly students from the University of Münster (two partici-
pants were employed in the health and service sector), took
part in this study. One participant expressed doubts about
the instructions and was excluded. A lottery-based monetary
reward for every randomly chosen fourth participant was paid
performance-contingently.
Experimental Task and Design
An established weight-holding persistence task (Hertel et al.,
2000) was administered in which effort is monotonously
related to performance regardless of ability or training. Partici-
pants were instructed to hold a 0.9kg weight with one hand
above a trip rod for as long as they felt comfortable. Each
participant performed four trials, two with each arm switching
the performing arm after each trial. The first two trials were
always performed individually. In the last two trials, partici-
pants worked either alone again (individual control condition),
with a group partner from whom they did not receive support
(group control condition) or with a group partner from whom
they received support (group condition with support). Thus, a
3 (task condition: individual control vs. group control vs. group
with support) × 2 (arm: dominant vs. non-dominant) × 2 (trial:
first vs. second trial with given arm) design was employed with
the last two factors being within-subjects.
Procedure
Before the session, participants were asked for any pre-existing
physical conditions, which would have led to the exclusion
from the experiment. Devices showing the time (watches and
mobile phones) were collected from the participants and
returned after the task. The task was explained leaving partici-
pants naïve about the exact number of trials and the group
sessions. Participants were instructed to perform as well as they
could, lowering their arm as soon as the task became too
Social support causes effort gains
Copyright © 2014 John Wiley & Sons, Ltd. Eur. J. Soc. Psychol. (2014)
uncomfortable to avoid injuries and total exhaustion. Written
permission for videotaping the entire session was taken and
recording started subsequently. The experimenter stayed in the
room during all sessions, located behind the performing partic-
ipant next to the video camera.
Following the first two individual trials, a group partner
was introduced in the two group conditions. In the group
control condition, the introduced partner was a trained female
confederate to control for social support in this condition. In
the group condition with support, the introduced group partner
was a participant who had performed the two individual trials
prior to the arrival of the second participant. As we were
interested in the type and amount of support people would
voluntarily provide in the employed group setting, we used
participants rather than a confederate in this condition.
In both group conditions, the first participant/confederate was
hidden behind a partition in the experimental room, wearing
headphones while the second participant was performing the
two individual trials to prevent dissemination of any information
from the individual trials. For the group trials, participants were
assigned a group name (“group blue”), and the real/second
participant was allegedly chosen at random to perform the persis-
tence task again. The other group partner was to stand on a marked
cross on the floor at a distance of 1.5 m and in a 45° angle in front
of the performing partner. In the group condition with support,
participants were further told that the other group member could
support her fellow group partner in whatever way she felt was
helpful except for helping to hold the weight. In the group control
condition, no reference to support was made. The confederate was
trained to act shy, avoiding explicit support of the performing
participant (e.g., avoiding eye contact, neither speaking nor
gesturing). In all group trials, the performing participant was not
allowed to communicate with her partner, and communication
was prohibited between the sessions. Performance feedback
was not provided between trials. Participants were furthermore
told that the group could, based on a lottery system, earn up to
€100 divided equally among the group partners. Every 10s of
holding the weight above the trip rod were worth €1.40.
In the individual control condition, the last two trials were
performed in the same manner as the first two trials except for
the introduced monetary reward of €0.70 for every 10 s of hold-
ing the weight above the trip rod resulting in a lottery-based re-
ward of up to €50. Dependent on the experimental condition and
the order of performance in the group conditions, the experiment
took 30–75 min. Rest periods between the first and the second
trial were 4 min, between the second and third trial 8 min, and
between the third and the fourth trial 6 min. After the last two
trials, participants were thanked and debriefed.
Measures
To investigate the type of support provided, the 22 sessions
of the group condition with support were rated by two
raters for social encouragement (i.e., expressed belief in
group members, cheering; e.g., “I am certain you will do
well on this task.”, clapping), social recognition (i.e., praise,
appreciation; e.g., “You are doing great.”), task-related
support (i.e., advice; e.g. “It helped me to count until 100.”),
and distraction (e.g., talking about something task-unrelated).
One point was scored for each act of support. The intraclass
correlation (two-way mixed) of the agreement between the
two employed raters (Shrout & Fleiss, 1979) was initially
.73, 95% CI [.59, .81], increasing to .99, 95% CI [.98, .99],
after their discussion of incongruent ratings.
Performance was defined as the total amount of seconds the
weight was held above the trip rod and measured by the
experimenter with a stop watch. A second independent rater
who was blind to the hypotheses recoded the performance
times from the videos. The intraclass correlation (two-way
mixed) as a measure of agreement between the experimenter
and the second rater (Shrout & Fleiss, 1979), .993, 95% CI
[.991, .995] showed close to perfect agreement.
To control whether received social support influenced percep-
tions of indispensability, the perceived importance of the own
contribution to the group outcome was assessed with two items
(“How important was your performance in the last trial?”and
“How important was your contribution for a good result during
the last trial?”) adopted from Hertel, Deter, and Konradt (2003)
and measured on a 7-point scale from 1 (not much) to 7 (very
much). The two items were highly correlated, r= .81, p<.001.
5
For exploratory reasons, we also investigated whether the
expected performance increase in the group condition with sup-
port was associated with increased stress levels. Experienced
strain was assessed with one item, which was adopted from Hertel
et al. (2000; “How strenuous was the last trial for you?”). It was
measured on an equivalent 7-point scale after each trial.
Results
A preliminary analysis of performance data of the individual
control condition in a 2 (start with arm: dominant vs.
nondominant) × 2 (kind of arm: dominant vs. nondominant) ×
2 (repetition: first vs. second trial with respective arm)
ANOVA with repeated measures on the last two factors
revealed a significant main effect for arm, F(1, 20) = 7.05,
p= .015, η
2
= 0.26. Performance was significantly higher with
the dominant arm (M= 167.7 s, SD = 60.3) than with the non-
dominant arm (M= 152.8 s, SD = 58.7). No other main or
interaction effects were observed, all Fs<1, suggesting that
performance was unaffected by the order of arms, and no
significant fatigue effect was present.
For the analysis of effort gains in groups, one overall
performance score was computed by subtracting average per-
formance times in the individual trials (first and second trial)
from the average performance times in the group trials (third
and fourth trial, cf. Hertel et al., 2000; Kerr, Feltz, & Irwin,
2012).
6
The difference scores thus entail the performance from
the individual trials as a theory consistent and clear baseline to
determine group-based effort gains and losses. Effort gains in
groups are indicated by positive difference scores. Please note
that effort gain scores were combined for the dominant and
nondominant arm based on a 3 (condition: individual control
5
One participant was excluded from all analyses of perceived indispensability
as her ratings were highly incongruent (i.e., she answered the two parallel
items in a diametrically opposed manner). The correlation of the two items de-
creased from .81 to .67 when including this participant.
6
An alternative analysis of effort gains in groups can be realized by considering
performance scores of individual trials as covariance in the main analysis of
performance in the group trials (cf. Kerr et al., 2008), thereby avoiding the
use of difference scores. Analyses following this approach led to an identical
results pattern.
Joachim Hüffmeier et al.
Copyright © 2014 John Wiley & Sons, Ltd. Eur. J. Soc. Psychol. (2014)
vs. group control vs. group with support) × 2 (arm: dominant
vs. nondominant arm) ANOVA with repeated measures on
the latter factor. There was a significant main effect for condi-
tion revealing significant differences between experimental
conditions, F(2, 63) = 15.77, p<.001, partial η
2
= 0.33. Neither
the main effect for arm nor the interaction was significant, all
Fs<1, indicating similar performance gains for both arms.
In a more detailed analysis of the effect for condition, a
priori contrasts (first contrast: group condition with support
[1], group control condition [1], individual control condition
[0]; second contrast: group condition with support [1], group
control condition [0], individual control condition [1])
yielded significantly higher increases in effort in the group
condition with support than in the group control condition,
t(63) = 4.51, p<.001, d= 1.35, and in the individual control
condition, t(63) = 5.16, p<.001, d= 1.45, consistent with
Hypothesis 3 (cf. Table 2). A post-hoc comparison of the
group control condition with the individual control condi-
tionrevealednosignificant difference, t<1.
Furthermore no significant difference occurred for perceived
indispensability for the group outcome, t(41) = 1.19, p= .24, and
for the strain measure, t<1, between the two group conditions
(cf. Table 2).
7
Finally, the video ratings of type of spontaneously
provided support showed that affective support (encouragement
and recognition; M= 26.73, SD = 23.34) clearly predominated in
the support condition compared with task-related support
(M=3.66, SD = 4.97), bias-corrected accelerated 95% CI
[15.09, 26.52] and distraction (M=6.55, SD = 5.65), bias-
corrected accelerated 95% CI [11.16, 24.34] (cf. Table 3).
8
Discussion
In line with Hypothesis 3, the results provide empirical
evidence for the assumed effect of fellow group members’
social support on individuals’performance: Receiving social
support increased performance beyond the levels of group
work without such support and also of individual work. These
experimental results extend previous correlational evidence
on social support in groups (e.g., Beehr et al., 2000; Chiaburu
& Harrison, 2008) by demonstrating actual group-based
performance gains on the individual level triggered by
social support.
Moreover, participants perceived themselves as equally
indispensable for the group outcome in both group conditions,
indicating that received support did not alter perceptions of
indispensability for the group (Kerr & Hertel, 2011). Noteworthy,
experienced strain was comparable in the two group conditions
despite the significant performance difference, reflecting
the well-documented positive effects of social support on
the stress–strain relation (e.g., S. Cohen & Wills, 1985;
Viswesvaran, Sanchez, & Fisher, 1999).
Based on previous research on social indispensability
(e.g., Hertel, Niemeyer, & Clauss, 2008; Kerr et al., 2007;
see also Kerr & Hertel, 2011), the lack of effort gains in the
group control condition as compared with individual work
may at first seem surprising. However, as assumed in Study
1, group settings incorporate in-group and reciprocity norms
(e.g., Gouldner, 1960; Tajfel, 1970; Wilder, 1986). The
neutral, that is, nonsupporting, group member might have
been perceived as violating the default expectations related
to social support in team settings and might therefore have
been demotivating and consequentially might have lowered
participants’effort in Study 3 to the level of individual work.
Finally, participants spontaneously provided mostly
affective social support, which may be partially due to the
employed, rather simple task, which did not require much
advice or assistance from group members. However, in line
Table 2. Means and standard deviations of performance scores (s) and subjective ratings (Study 3; N= 88)
Group with support Group control Individual control
Measure M SD M SD M SD
Performance
Individual Trials 1 and 2 169.75 64.96 172.23 36.37 160.30 57.26
Difference scores 62.11 46.22 7.75 33.14 0.09 39.60
Strain
Individual Trials 1 and 2 4.43 1.53 4.27 1.10 3.82 1.42
Difference scores 1.16 1.04 1.05 1.08 1.20 0.80
Perceived indispensability 6.12 1.06 5.76 0.91 5.11 1.23
Trials 3 and 4
7
Results showed a similar pattern, t(42) = 0.85, p= .40, when including the
participant with incongruent ratings for perceived indispensability.
Table 3. Means and standard deviations of social support provided (Study 3, N= 22)
Type of support
Encouragement Recognition Task-related Rest category
Component M SD M SD M SD M SD
Verbal 7.70 5.73 9.41 7.71 2.36 2.77 4.07 3.38
Nonverbal 4.93 6.33 4.68 6.54 1.30 2.44 2.47 2.57
8
For an exploratory analysis of the distinctive predictive effects of the amount of af-
fective and task-related support on effort gains, we calculated linear regression anal-
yses. Results revealed affective support as a marginal predictor of effort gains in
groups, R
2
= .095, F(1, 20) = 2.10, p= .082 (one-tailed), and task-related support
as a not significant predictor of effort gains in groups, F<1. These effects were ob-
served with a relatively small sample size in this condition (N= 22). Note, however,
that they nevertheless tend to be consistent with our theoretical model hypothesizing
affective support as primary predictor of effort gains in groups.
Social support causes effort gains
Copyright © 2014 John Wiley & Sons, Ltd. Eur. J. Soc. Psychol. (2014)
with Study 1 and the MSST (Hüffmeier & Hertel, 2011),
participants might have also provided more affective support
because they believed affective support to be particularly
effective in enhancing effort of others.
GENERAL DISCUSSION
The objective of the present research was to explore receiving
social support as unique and so far understudied source of effort
gains in groups. Consistent with our general framework (cf.
Hüffmeier & Hertel, 2011), our results not only showed that
social support is evident in people’s beliefs about motivating
group work, but that receiving social support also substantially
increases effort intentions and performance compared with
group work without support and individual work. Notably, the
effects of fellow group members’support were consistently
demonstrated across different samples (employees, active
athletes, and university students) and across different tasks.
Moreover, the effect sizes for the demonstrated effort gains
in groups indicate quite large effects (cf. J. Cohen, 1992),
suggesting that receiving social support can be a particularly
strong motivator. Descriptively, the magnitude of the obtained
effect of social support in Study 3, g= 1.42 (comparing group
work with support to individual work), was even stronger
than previously established sources of effort gains: social
comparison, g= 0.41 (Weber & Hertel, 2007), social indis-
pensability, g= 0.31 (Weber & Hertel, 2007), and social
compensation, g= 0.69 (Karau & Williams, 1993).
Importantly, the observed effects of social support are dis-
tinct from mere social facilitation effects (Zajonc, 1965). In
the individual trials with one nonperforming person present
—the coach (Study 2) or the experimenter (Study 3)—facilitating
effects due to evaluation apprehension (e.g., Feinberg &
Aiello, 2006; Guerin, 1986) were presumably present.
Introducing a supporting group partner increased effort well
beyond this level of individual work revealing additional effort
resulting from social support. Furthermore, perceived indis-
pensability for the group outcome (e.g., Hertel et al., 2000;
Kerr & Hertel, 2011) can neither account for the demonstrated
effects. In Studies 2 and 3, we controlled for social indispensa-
bility rendering the performing participant in the group
conditions with and without support highly indispensable for
the group outcome. The supporting group partner triggered
additional effort beyond the level observed in the group
condition without support, indicating that indispensability
cannot account for the obtained effect. Finally, the similar results
of indispensability ratings in the two group conditions (Study 3)
are also inconsistent with this alternative explanation.
The present research is limited in several ways. The
conducted studies demonstrate a strong effect of social support
on effort intentions and performance measures. However, the
psychological processes underlying this effect as specified by
the MSST (Hüffmeier & Hertel, 2011) were not assessed.
The MSST assumes that affective social support leads to effort
gains through individual level processes such as increased
self-efficacy (Bandura, 1991) or goal setting (Locke &
Latham, 1990) and through group level processes as cohesion
and group identification (van Dick, Tissington, & Hertel,
2009). Task-related support is assumed to operate mainly
through learning and reciprocation processes within the group
(Hüffmeier & Hertel, 2011). Future research is required to
further investigate these processes.
Moreover, the research designs employed in Studies 2 and
3 did not allow for a specific test of the distinctive predictive
effects of affective support and task-related support. As this
was, however, not the aim of this first research on the motivating
effects of fellow group members’support, future research
should differentiate between the motivating effects of affective
and task-related support. Furthermore, the demonstrated effects
on performance were found employing a terminated, simple
physical task with an unfamiliar fellow group member.
Replications of these findings in more complex and long-term
tasks with existing and larger groups are desirable. Future
research could furthermore investigate, which combination of
single factors (e.g., the number of supporters, the quantity of
support provided, the support timing, etc.) is most meaningful
in triggering effort gains in individual group members.
Moreover, Study 2 indeed indicated similar motivational
effects for women and men receiving fellow group members’
social support. It is, however, conceivable that characteristics
of the provider of social support, such as, for instance, gender
and the associated behavior expectations (cf. Eagly &
Crowley, 1986), might moderate the effect of receiving fellow
group members’social support on effort. Demonstrating the
motivating effects of fellow group members’social support
among gender-heterogeneous groups would thus further aid
in generalizing the obtained findings.
Finally, the effects of social support on effort intentions and
performance were investigated in separate studies in order to
avoid mere-measurement effects (e.g., Morwitz, Johnson, &
Schmittlein, 1993; Sherman, 1980; Sprott, Spangenberg, &
Fisher, 2003). Asking participants about a certain behavior
or intention might change subsequent behavior, as
‘people are reminded of what they should do when making
predictions and then act in a way that is consistent with norma-
tive prescriptions to a greater or lesser degree than they would
have absent making a prediction’(Sprott et al., 2003, p. 423).
Thus, showing that social support affects both intentions and
behavior in a similar way might be more conservative (and thus
conclusive) in separate studies that avoid mere-measurement
effects. However, it might be valuable to investigate whether
merely asking participants about their intended effort increases
their exerted effort significantly and thus benefits a subsequent
group task.
Future research might also address motivating effects of
social support for the providing group members. As has been
shown in research on altruism and helping behavior
(e.g., Weinstein & Ryan, 2010), supporting others might have
immediate payoffs for persons’self-esteem in addition to more
strategic consequences within groups, such as higher status,
respect, or popularity. Moreover, mutual exchange of social
support might contribute to higher cohesion and trust at the group
level (see also related research on positive effects of organizational
citizenship behaviors at the group level, for example, Podsakoff
et al., 2009). Research on suchemergingstatesduetospecific
interactions within groups is highly needed in order to better
understand the development of groups across time (e.g., Kozlowski
& Bell, 2013).
Joachim Hüffmeier et al.
Copyright © 2014 John Wiley & Sons, Ltd. Eur. J. Soc. Psychol. (2014)
However, social support might not automatically lead to in-
creased motivation and performance. Receiving support from
an unfamiliar and clearly superior group member might, for
example, be interpreted as condescending advice and be
rejected, which might then undermine the motivating effects
of support (cf. Irwin et al., 2013). Additionally, following
Social Impact Theory (Latané, 1981), an increasing number
of possible targets of the provided support might decrease
the effectiveness of support in triggering additional effort.
Furthermore, feeling not specifically addressed by the
provided support (cf. also Irwin et al., 2013) might diminish
motivating effects of social support. Moreover, providing high
social support permanently might not only lead to sucker
effects (Kerr, 1983) or to aversive effects but also to exhaus-
tion and burnout. Thus, curvilinear relations between social
support and motivation or well-being (see e.g., Burnett,
Chiaburu, Shapiro, & Li, 2013, for curvilinear effects of
perceived organizational support) are plausible and fruitful to
explore (e.g., Pierce & Aguinis, 2013).
Taken together, the present research demonstrates that
receiving fellow group members’social support is a unique
and strong source of increased effort intentions and perfor-
mance for group members. The considerable effect sizes and
the lack of systematic research on motivating effects of
dynamic group interactions warrant further specific investiga-
tions of the effect of fellow group members’social support
and its context conditions. Moreover, group leaders might
want to increase group members’awareness of the benefits of
social support and encourage them to offer regular support to
one another to establish an atmosphere of mutual support. In ad-
dition to other sources of additional effort in groups, social sup-
port offers an “easy and inexpensive mean[s]”to improve work
effectiveness (Osca et al., 2005, p. 307). Therefore, creating a
positive group climate and an atmosphere of mutual support
among group members might increase group members’motiva-
tion and performance substantially.
ACKNOWLEDGEMENT
This research has been supported by a grant from the Deutsche
Forschungsgemeinschaft (He 2745/8-4) to the last author.
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